| AUTOwrXER | 01-18-2006 02:23 PM |
Going completely off topic here, but something I've always wondered about...
Does anyone know how the cockpit adjustable sway bars on purpose-built race cars work?
Does anyone know how the cockpit adjustable sway bars on purpose-built race cars work?
| trhoppe | 01-18-2006 02:32 PM |
Like this
[url]http://www.hrpworld.com/index.cfm?form_prod_id=217,212,363_1432&action=product[/url]
[img]http://www.hrpworld.com/client_images/ecommerce/client_39/products/1436_hdr.jpg[/img]
This blade arm turns. When its on the flat side, its easier to bend so therefore the bar is softer. When its on the thin side, its much harder to bend so its stiffar.
-Tom
[url]http://www.hrpworld.com/index.cfm?form_prod_id=217,212,363_1432&action=product[/url]
[img]http://www.hrpworld.com/client_images/ecommerce/client_39/products/1436_hdr.jpg[/img]
This blade arm turns. When its on the flat side, its easier to bend so therefore the bar is softer. When its on the thin side, its much harder to bend so its stiffar.
-Tom
| Draken | 01-18-2006 02:47 PM |
Joel: Most of what I've seen involves the end link sliding on the lever arm portion of the bar. At least that's what I've seen on some little Formula cars.
Sample:
[img]http://www.subrew.com/tmp/rollbar1.jpg[/img]
I've seen this style end link with a standard control cable connected to it. Also, I've seen this style end link with a nice tightening knob that locked it in place. Would make for simple "pop under the car" adjustments.
Hoppe's link is cool. But he's still a *****.
Chris H.
Sample:
[img]http://www.subrew.com/tmp/rollbar1.jpg[/img]
I've seen this style end link with a standard control cable connected to it. Also, I've seen this style end link with a nice tightening knob that locked it in place. Would make for simple "pop under the car" adjustments.
Hoppe's link is cool. But he's still a *****.
Chris H.
| AUTOwrXER | 01-18-2006 03:05 PM |
Also, all my notes are at my desk at home, but the bar is actually 1 and 1/4" tube with 3/16" wall thickness. Therefore O.D. = 31.75mm and I.D. = 22.225mm.
| AUTOwrXER | 01-18-2006 03:08 PM |
[QUOTE=trhoppe]Like this
[url]http://www.hrpworld.com/index.cfm?form_prod_id=217,212,363_1432&action=product[/url]
[img]http://www.hrpworld.com/client_images/ecommerce/client_39/products/1436_hdr.jpg[/img]
This blade arm turns. When its on the flat side, its easier to bend so therefore the bar is softer. When its on the thin side, its much harder to bend so its stiffar.
-Tom[/QUOTE]
That's pretty hawt. I'd like an adjustable rear bar that a co-driver could yank on corner entry and then set soft at corner exit. I guess that's what the WRC teams were trying to do with their active bars...
[url]http://www.hrpworld.com/index.cfm?form_prod_id=217,212,363_1432&action=product[/url]
[img]http://www.hrpworld.com/client_images/ecommerce/client_39/products/1436_hdr.jpg[/img]
This blade arm turns. When its on the flat side, its easier to bend so therefore the bar is softer. When its on the thin side, its much harder to bend so its stiffar.
-Tom[/QUOTE]
That's pretty hawt. I'd like an adjustable rear bar that a co-driver could yank on corner entry and then set soft at corner exit. I guess that's what the WRC teams were trying to do with their active bars...
| 10th Warrior | 01-18-2006 04:40 PM |
[quote]I'd like an adjustable rear bar that a co-driver could yank on corner entry and then set soft at corner exit. I guess that's what the WRC teams were trying to do with their active bars...[/quote]
except they had the computer do it ;)
except they had the computer do it ;)
| Au_STi | 01-18-2006 05:06 PM |
I have an '04 STi w/Strano fsb with no rubbing issues and haven't looked under an '05 yet. If I understand the issue correctly, on some '05-'06 STi's there is a rubbing issue with a power steering bolt due to either bolt head length/production year changes/tolerances. Looking under my car, if I was still running in SCCA A-Stock and had this issue I would shim out the swaybar body mount bracket 1/16"-1/8" as suggested by WRX_orlando and PossumK as swaybar mounting is free in Stock class. I would probably use a piece of sheetmetal under the entire bushing/bushing mounting bracket instead of washers/shims, just my preference. Is there room between the bar and brace on the '05-'06's to do this? There is on an '04.
Andy Hohl
Andy Hohl
| Draken | 01-18-2006 05:14 PM |
I had to go by home during a site visit, so i popped under my STi and measured the Whiteline bar. Using the anti-roll bar formula as published in Fred Puhn's book "How to make your car handle" i came up with the following calcs.
[COLOR=Red]Formula:
K (lbs/in) = 500,000 x (D^4 - d^4) / (0.4244 x A^2 x B) + (0.2264 x C^3)
D = outer bar diameter
d = inner bar diameter
A = length of bar end, lever arm
B = length of center section
C = length of bar end (if 90-degree bend, C = A)[/COLOR]
Whiteline Bar, soft setting: K = ~ 1,307 lbs/in.
D = 1.063"
d = na
A = 5.5"
B = 32"
C = 7"
Whiteline Bar, stiff setting: K = ~ 1,731 lbs/in. (34% stiffer than soft setting)
D = 1.063"
d = na
A = 4.75"
B = 32"
C = 6.5"
Based on the photos supplied above, it looks like the major changes in the Strano bar include a longer center section (est. 4") and a longer lever arm (estimate 1" longer than Whiteline stiff setting.) Also, the Strano bar uses a 90-degree bend.
[B]Estimated[/B] Strano Bar: K = ~ 1,655 lbs/in.
D = 1.250"
d = 0.875"
A = 5.75" (based on photos above, lever arm is roughly 1" longer)
B = 36" (based on photos above, center section is roughly 2" longer per side)
C = 6.25"
If anyone has specific measurements of the Strano bar for items A and B, that would be great.
Chris H.
[COLOR=Red]Formula:
K (lbs/in) = 500,000 x (D^4 - d^4) / (0.4244 x A^2 x B) + (0.2264 x C^3)
D = outer bar diameter
d = inner bar diameter
A = length of bar end, lever arm
B = length of center section
C = length of bar end (if 90-degree bend, C = A)[/COLOR]
Whiteline Bar, soft setting: K = ~ 1,307 lbs/in.
D = 1.063"
d = na
A = 5.5"
B = 32"
C = 7"
Whiteline Bar, stiff setting: K = ~ 1,731 lbs/in. (34% stiffer than soft setting)
D = 1.063"
d = na
A = 4.75"
B = 32"
C = 6.5"
Based on the photos supplied above, it looks like the major changes in the Strano bar include a longer center section (est. 4") and a longer lever arm (estimate 1" longer than Whiteline stiff setting.) Also, the Strano bar uses a 90-degree bend.
[B]Estimated[/B] Strano Bar: K = ~ 1,655 lbs/in.
D = 1.250"
d = 0.875"
A = 5.75" (based on photos above, lever arm is roughly 1" longer)
B = 36" (based on photos above, center section is roughly 2" longer per side)
C = 6.25"
If anyone has specific measurements of the Strano bar for items A and B, that would be great.
Chris H.
| leecea | 01-18-2006 05:34 PM |
In many cases, using different mounting holes to change the bar's lever arm results in a change in angle of the endlinks.
Although I'm not 100% sure, I do think this will change the calculation since an endlink that is not vertical will result in some of the force being tranmitted as a horizontal load on the hub and/or bar mounts and not all the sway bar's resistance is translated into vertical force.
If you know the endlink's angle, simple trig can be used to resolve the force into vertical and horizontal, but I'm not sure if that simple method is good enough for a moving system.
Although I'm not 100% sure, I do think this will change the calculation since an endlink that is not vertical will result in some of the force being tranmitted as a horizontal load on the hub and/or bar mounts and not all the sway bar's resistance is translated into vertical force.
If you know the endlink's angle, simple trig can be used to resolve the force into vertical and horizontal, but I'm not sure if that simple method is good enough for a moving system.
| Scott Farmer | 01-18-2006 05:49 PM |
[QUOTE=dowroa]Mine doesn't squeak. In fact, my Strano bar squeaks LESS than the Whiteline bar I had due to the solid endlinks. I was using the stockers, but the Strano bar endlink design is what I like TONS better.
I have been thinking about polyeurathane bushings though... might be too much sheer stress on that bolt though.
- dow[/QUOTE]
However, he has the exact same bar I had (we swapped bars) on an 05 STi (same as mine). Whereas he has no squeaks, mine squeaked constantly. I tried several different endlink lubes and the other fixes suggested here.
This should speak to the wide variations even within the same year.
Mine did not, however, impact the aforementioned bolt.
I have been thinking about polyeurathane bushings though... might be too much sheer stress on that bolt though.
- dow[/QUOTE]
However, he has the exact same bar I had (we swapped bars) on an 05 STi (same as mine). Whereas he has no squeaks, mine squeaked constantly. I tried several different endlink lubes and the other fixes suggested here.
This should speak to the wide variations even within the same year.
Mine did not, however, impact the aforementioned bolt.
| dowroa | 01-18-2006 06:37 PM |
[QUOTE=Scott Farmer]However, he has the exact same bar I had (we swapped bars) on an 05 STi (same as mine). Whereas he has no squeaks, mine squeaked constantly. I tried several different endlink lubes and the other fixes suggested here.
This should speak to the wide variations even within the same year.
Mine did not, however, impact the aforementioned bolt.[/QUOTE]
And, just for verification, it is clear of my bolt as well.
- dow
This should speak to the wide variations even within the same year.
Mine did not, however, impact the aforementioned bolt.[/QUOTE]
And, just for verification, it is clear of my bolt as well.
- dow
| crystalhelix | 01-18-2006 06:59 PM |
I talked to Sam yesterday, he's looking into why people would be having an issue. I haven't been under the car but I don't have any squeaking or squacking.
J
J
| VR62STI | 01-18-2006 07:49 PM |
Dear Sam (STRANO):
When you registered did you receive an immediate email from NASIOC? They send out a validation link to the email you specify, and you have to click it for registration to commence. Either your email account blocked this mail, or the address was entered incorrectly. I suggest signing up for gmail or hotmail, and then trying to reregister with a new name - like NASIOC-tech-SUXORS-ma-BALLZORS.
If this isn't the problem then maybe your browser is blocking cookies or something. Use Mozilla instead; its nicer anyway.
ps. I like my bar just fine!
When you registered did you receive an immediate email from NASIOC? They send out a validation link to the email you specify, and you have to click it for registration to commence. Either your email account blocked this mail, or the address was entered incorrectly. I suggest signing up for gmail or hotmail, and then trying to reregister with a new name - like NASIOC-tech-SUXORS-ma-BALLZORS.
If this isn't the problem then maybe your browser is blocking cookies or something. Use Mozilla instead; its nicer anyway.
ps. I like my bar just fine!
| Crash477 | 01-18-2006 10:41 PM |
[QUOTE=trhoppe]Ok, just one quick comment with no disrespect meant.
Its a 32mm bar people. Its made to fit and stuffed into a spot that was reserved for a stock 19mm bar. Its a MOTORSPORTS part, not a daily driver part (although it *can* be used that way). Expect some noise, expect some clunking, expect some squeaking.
-Tom
(arsehole)[/QUOTE]
Agreed!
Its a 32mm bar people. Its made to fit and stuffed into a spot that was reserved for a stock 19mm bar. Its a MOTORSPORTS part, not a daily driver part (although it *can* be used that way). Expect some noise, expect some clunking, expect some squeaking.
-Tom
(arsehole)[/QUOTE]
Agreed!
| z3coupe | 01-19-2006 04:22 AM |
FWIW, my Strano bar does make squish type of noises, mostly when going over speed bumps at low speeds. But for the record, I am not complaining about that. As was mentioned, it is a motorsports part. I can live with the noises (unlike the holy hell my old Zeals were making). My whole reason for this post was the worry that the bolt rubbing on the bar could later become a safety issue, not complaining about cosmetic or bothersome noises. And in order for this to not escalate into a safety issue for Sam or Addco, wanted this brought to their attention - but FIRST I wanted to see how many others were having the same problem. As I stated, if it were just a local problem with our install, then fine. But if there were more with this problem (and who would know unless you KNEW to look for it), then it would be improtant enough for them to look into what is happening. I HOPE some can understand that.
| RebelINS | 01-19-2006 05:36 AM |
As far as specific calcs about how stiff one bar is compared to another, I don't understand how a simple formula could tell you that. The only way I could see this working is if the two bars were made out of the exact same material, had the exact same attaching location, and had bends at the exact same spot. Otherwise, I would think you would need to make a free body diagram in 3D and know the material composition of each bar, or by using some advanced software. If not, I'm curious how you go about doing it.
-Wes
-Wes
| Big C | 01-19-2006 08:01 AM |
I admit I didn't read this entire thread but the problem could be solved in a small amount of time with a grinder or file. You wouldn't compromise anything other than a few mm of the head of the bolt.
FWIW- If you intend to survive in the car hobby past installing blingtastic rims/tires you need to understand that almost nothing in the automotive aftermarket works/fits/looks like OEM. If you need that level fit/finish you should probably stick with stock parts. :rolleyes:
-C
FWIW- If you intend to survive in the car hobby past installing blingtastic rims/tires you need to understand that almost nothing in the automotive aftermarket works/fits/looks like OEM. If you need that level fit/finish you should probably stick with stock parts. :rolleyes:
-C
| BlkWRXWag | 01-19-2006 10:32 AM |
[QUOTE=Big C]FWIW- If you intend to survive in the car hobby past installing blingtastic rims/tires you need to understand that almost nothing in the automotive aftermarket works/fits/looks like OEM. If you need that level fit/finish you should probably stick with stock parts. :rolleyes:
-C[/QUOTE]
I was asking what the fix was, not complaining that it did not fit like the OEM bar? I'm also sorry that you're offended by my "blingtastic rims/tires".
-C[/QUOTE]
I was asking what the fix was, not complaining that it did not fit like the OEM bar? I'm also sorry that you're offended by my "blingtastic rims/tires".
| Big C | 01-19-2006 11:45 AM |
I was addressing the whining in post #34. Unless you = z3coupe there should be no problem.
My point still stands unless someone knows an aftermarket company who's every part fits correctly as delivered.....I've never seen one in ~15 years of screwing around with cars.
-C
My point still stands unless someone knows an aftermarket company who's every part fits correctly as delivered.....I've never seen one in ~15 years of screwing around with cars.
-C
| BlkWRXWag | 01-19-2006 11:52 AM |
Can people please be clear who they are insulting - I've obvioulsy got some kind of inferiority complex going on where I always think it is me :D Thank you!
| AtomicRacer | 01-19-2006 11:58 AM |
I would like to see actual weights posted of the Strano Bar without endlinks. I would also like to know the weight of each endlink (complete with brackets).
Same for the whiteline bar, how much does it weigh (without endlinks)? How much do the factory endlinks weigh?
Thanks,
-Paul
Same for the whiteline bar, how much does it weigh (without endlinks)? How much do the factory endlinks weigh?
Thanks,
-Paul
| AUTOwrXER | 01-19-2006 12:06 PM |
[QUOTE=Draken]I had to go by home during a site visit, so i popped under my STi and measured the Whiteline bar. Using the anti-roll bar formula as published in Fred Puhn's book "How to make your car handle" i came up with the following calcs.
[COLOR=Red]Formula:
K (lbs/in) = 500,000 x (D^4 - d^4) / (0.4244 x A^2 x B) + (0.2264 x C^3)
D = outer bar diameter
d = inner bar diameter
A = length of bar end, lever arm
B = length of center section
C = length of bar end (if 90-degree bend, C = A)[/COLOR]
Whiteline Bar, soft setting: K = ~ 1,412 lbs/in.
D = 1.063"
d = na
A = 5.25"
B = 32"
C = 7"
Whiteline Bar, stiff setting: K = ~ 1,893 lbs/in. (34% stiffer than soft setting)
D = 1.063"
d = na
A = 4.5"
B = 32"
C = 6.5"
Based on the photos supplied above, it looks like the major changes in the Strano bar include a longer center section (est. 4") and a longer lever arm (estimate 1" longer than Whiteline stiff setting.) Also, the Strano bar uses a 90-degree bend.
[B]Estimated[/B] Strano Bar: K = ~ 1,856 lbs/in.
D = 1.250"
d = 0.875"
A = 5.5" (based on photos above, lever arm is roughly 1" longer)
B = 36" (based on photos above, center section is roughly 2" longer per side)
C = 5.5' (design uses a 90-degree bend)
If anyone has specific measurements of the Strano bar for items A and B, that would be great.
Chris H.[/QUOTE]
I don't have the Strano bar in front of me, but for one the bend is not 90*. As most steel compositions have a very similar MOE, I agree that we can neglect the effects of different material types.
leecea's question is interesting, however. With the different endlink angle, how much of the verticle force from the motion of the CA is going toward twisting the bar. If the endlink was exactly horizontal, I would assume that it is not transfering any force in the vertical direction. We would need to know the angle of the endlink to make that comparison. Likewise the angle of the Strano endlink changes with CA movement (as we see clearly at full droop).
This is looking more and more like only a dynamic model would tell the full story.
[COLOR=Red]Formula:
K (lbs/in) = 500,000 x (D^4 - d^4) / (0.4244 x A^2 x B) + (0.2264 x C^3)
D = outer bar diameter
d = inner bar diameter
A = length of bar end, lever arm
B = length of center section
C = length of bar end (if 90-degree bend, C = A)[/COLOR]
Whiteline Bar, soft setting: K = ~ 1,412 lbs/in.
D = 1.063"
d = na
A = 5.25"
B = 32"
C = 7"
Whiteline Bar, stiff setting: K = ~ 1,893 lbs/in. (34% stiffer than soft setting)
D = 1.063"
d = na
A = 4.5"
B = 32"
C = 6.5"
Based on the photos supplied above, it looks like the major changes in the Strano bar include a longer center section (est. 4") and a longer lever arm (estimate 1" longer than Whiteline stiff setting.) Also, the Strano bar uses a 90-degree bend.
[B]Estimated[/B] Strano Bar: K = ~ 1,856 lbs/in.
D = 1.250"
d = 0.875"
A = 5.5" (based on photos above, lever arm is roughly 1" longer)
B = 36" (based on photos above, center section is roughly 2" longer per side)
C = 5.5' (design uses a 90-degree bend)
If anyone has specific measurements of the Strano bar for items A and B, that would be great.
Chris H.[/QUOTE]
I don't have the Strano bar in front of me, but for one the bend is not 90*. As most steel compositions have a very similar MOE, I agree that we can neglect the effects of different material types.
leecea's question is interesting, however. With the different endlink angle, how much of the verticle force from the motion of the CA is going toward twisting the bar. If the endlink was exactly horizontal, I would assume that it is not transfering any force in the vertical direction. We would need to know the angle of the endlink to make that comparison. Likewise the angle of the Strano endlink changes with CA movement (as we see clearly at full droop).
This is looking more and more like only a dynamic model would tell the full story.
| AUTOwrXER | 01-19-2006 12:10 PM |
Actually, Chris, I think you are using the formula for the spring rate of the bar, which is different than comparing the force the bars will transfer between the wheels. In the past I've used moment of inertia calculations to compare bars, though knowing the spring rate of the bar is nice when choosing main springs.
| Pacobeagle | 01-19-2006 12:51 PM |
Has anyone thought of switching the hex-head bolt to an allen-head? This way, the top of the bolt(mushroom looking) gives you more clearance on the sway-bar.
just my .02
Jose
Japtrix.com
just my .02
Jose
Japtrix.com
| D_REX | 01-19-2006 12:56 PM |
[QUOTE=Pacobeagle1]allen-head[/QUOTE]
AKA Socket Head
AKA Socket Head
| Draken | 01-19-2006 01:07 PM |
Joel: I'm actually using a very standard rate for calculating the spring rate of a torsion bar, which is what an anti-roll bar is. The basic formula has been modified to suit the needs of anti-roll bars, and i chose this specific Fred Puhn verson cause it came up on the first page in my google search :) Honestly, it has been WAY too long since engineering school for me to pull out my moments calcs. That's why i listed my calcs, cause i'm not trying to prove/hide anything. i am just curious about the bar's specs.
With regard to the non 90-degree bend of the end, I was only going off this photo: [url]http://mere.darg.net/sti-fsb/pinkfsb_002[/url]
Altering the calcs to assume a non-90 degree bend, such as 80-85 degrees, actually softens it more. But now we are talking about single digit % differences.
The idea of the 32mm tube is great as it does provide considerably more cross sectional area than the 27mm whiteline bar. I am, however, curious why the center section is wider than stock, and why the lever arm appears to be longer, even longer than stock based on my stock bar in the garage. If the lever arm length was chosen to give a near vertical placement of the end link during loaded conditions, then I could see things changing a little. But as shown, a simple 3/4 to 1" change of this dimension alone would change the bar's stiffness ~ 30%, plus or minus given any changes of end link angle. Which may be way too much for your needs, but...well..it is what I had assumed the bar was rated at over the whiteline bar. And was/is going to be my choice of bar should i decide i want more roll stiffness.
Chris H.
With regard to the non 90-degree bend of the end, I was only going off this photo: [url]http://mere.darg.net/sti-fsb/pinkfsb_002[/url]
Altering the calcs to assume a non-90 degree bend, such as 80-85 degrees, actually softens it more. But now we are talking about single digit % differences.
The idea of the 32mm tube is great as it does provide considerably more cross sectional area than the 27mm whiteline bar. I am, however, curious why the center section is wider than stock, and why the lever arm appears to be longer, even longer than stock based on my stock bar in the garage. If the lever arm length was chosen to give a near vertical placement of the end link during loaded conditions, then I could see things changing a little. But as shown, a simple 3/4 to 1" change of this dimension alone would change the bar's stiffness ~ 30%, plus or minus given any changes of end link angle. Which may be way too much for your needs, but...well..it is what I had assumed the bar was rated at over the whiteline bar. And was/is going to be my choice of bar should i decide i want more roll stiffness.
Chris H.
| sstrano | 01-19-2006 01:32 PM |
Thank you to those who recommended trying an alternate e-mail address. That worked, and here I am!!!
I tend not to pull punches, and I don't intend to here either.
First, it's simple match that a 32mm hollow bar is stiffer than a 27mm solid bar. Bar stiffness is derived from the OD to the 4th power. The inside of a hollow bar doesn't do all that much because it flexes much less than the outside. Hence the reasons all races cars use hollow bars. It's weight you need not drag around.
Secondly, I hadn't seen a Whiteline 27 in person, but had seen their other bars in person, and had heard from folks I trust that the bar was the same design. Someone was nice enough to have posted a picture of a Whiteline bar, in which you can see that the lever arm is not shortened at all. No matter what hole you run, the force still goes straight down into the bar. You don't get more leverage on a pry bar that's bend vs. one that is straight. The lever arm is just not shortened on a Whiteline front bar. Rear bars are very different in that moving the endlink does change the lever arm length of the bar, which is why you see many adjustable rears, and no other adjustable fronts. Everyone else knows the front can't be adjustable with the design Whiteline has.
Thirdly, the issue of the metal came up. While there are alloys of steel that have more strength, most all steels are very much the same in terms of flex strength, which is what bars do. Chrome-Moly for instance is of no help in a swaybar.
The weight of the bar was addressed in the original thread. Minus links it's about 9 pounds.
Here's the bottom line:
My bar is 32mm, made for me by a reputable swaybar company that's been around for a long time. It is not adjustable because it cannot be adjustable, and just because other companies will claim their bar is, won't make me lie or make something that really doesn't work just to keep up. Even if a front bar like Whiteline's did shorten the lever arm (which is doesn't), the length is not shortened by enough to change the rate of a 27mm bar to what you'd get from a 29mm bar. My bar works, most everyone who has it, really likes it. Nobody thought a bar like this would work, I've proved it does on a car like a Subaru.
If you don't want to use our bar, that's fine.... but your decision should be made with accurate information, and the idea that the Whiteline bar actually shortens the lever arm is not at all accurate. Further, the fitment issue seems to only be happening on very few cars as the number of folks who have the bar and DON'T rub can attest (and have).
Variety makes the world go 'round folks. :)
I tend not to pull punches, and I don't intend to here either.
First, it's simple match that a 32mm hollow bar is stiffer than a 27mm solid bar. Bar stiffness is derived from the OD to the 4th power. The inside of a hollow bar doesn't do all that much because it flexes much less than the outside. Hence the reasons all races cars use hollow bars. It's weight you need not drag around.
Secondly, I hadn't seen a Whiteline 27 in person, but had seen their other bars in person, and had heard from folks I trust that the bar was the same design. Someone was nice enough to have posted a picture of a Whiteline bar, in which you can see that the lever arm is not shortened at all. No matter what hole you run, the force still goes straight down into the bar. You don't get more leverage on a pry bar that's bend vs. one that is straight. The lever arm is just not shortened on a Whiteline front bar. Rear bars are very different in that moving the endlink does change the lever arm length of the bar, which is why you see many adjustable rears, and no other adjustable fronts. Everyone else knows the front can't be adjustable with the design Whiteline has.
Thirdly, the issue of the metal came up. While there are alloys of steel that have more strength, most all steels are very much the same in terms of flex strength, which is what bars do. Chrome-Moly for instance is of no help in a swaybar.
The weight of the bar was addressed in the original thread. Minus links it's about 9 pounds.
Here's the bottom line:
My bar is 32mm, made for me by a reputable swaybar company that's been around for a long time. It is not adjustable because it cannot be adjustable, and just because other companies will claim their bar is, won't make me lie or make something that really doesn't work just to keep up. Even if a front bar like Whiteline's did shorten the lever arm (which is doesn't), the length is not shortened by enough to change the rate of a 27mm bar to what you'd get from a 29mm bar. My bar works, most everyone who has it, really likes it. Nobody thought a bar like this would work, I've proved it does on a car like a Subaru.
If you don't want to use our bar, that's fine.... but your decision should be made with accurate information, and the idea that the Whiteline bar actually shortens the lever arm is not at all accurate. Further, the fitment issue seems to only be happening on very few cars as the number of folks who have the bar and DON'T rub can attest (and have).
Variety makes the world go 'round folks. :)
| crystalhelix | 01-19-2006 01:33 PM |
If someone can send me a sketch with dimensions of each bar that would be nice. I already have a model of the strano bar, I don't know the dimensions on the whiteline. I already have my bar on the car so it would take me a bit to remeasure. I can do a Finite Element Analysis on both bars as long as I know the material they are made of and their dimensions. [B]I think with common sense though the strano bar would be stiffer because it has more straight sections that will flex less[/B]. The offer's in the air and it wouldn't take me long at all, I just need dimensions and materials. I can even do videos of teh bars flexing under stress "virtual" reality like. Pm me or send an email.
Justin
PS -welcome to the boards sam, looks like you worked something out, lol.
Justin
PS -welcome to the boards sam, looks like you worked something out, lol.
| AUTOwrXER | 01-19-2006 03:41 PM |
Welcome Sam.
Justin - I'll leave this to you as I left my engineering career at the graduation ceremony. Looks like you're less rusty.
Justin - I'll leave this to you as I left my engineering career at the graduation ceremony. Looks like you're less rusty.
| AtomicRacer | 01-19-2006 03:44 PM |
[QUOTE=sstrano]
Secondly, I hadn't seen a Whiteline 27 in person, but had seen their other bars in person, and had heard from folks I trust that the bar was the same design. Someone was nice enough to have posted a picture of a Whiteline bar, in which you can see that the lever arm is not shortened at all. No matter what hole you run, the force still goes straight down into the bar. You don't get more leverage on a pry bar that's bend vs. one that is straight. The lever arm is just not shortened on a Whiteline front bar. Rear bars are very different in that moving the endlink does change the lever arm length of the bar, which is why you see many adjustable rears, and no other adjustable fronts. Everyone else knows the front can't be adjustable with the design Whiteline has.
[/QUOTE]
Once installed it sure appears to me that it would shorten the level arm between the two holes offered. I have not measured it but it appears to be about 3/4" from memory.
I will say this, the thing is damn heavy.
-Paul
Secondly, I hadn't seen a Whiteline 27 in person, but had seen their other bars in person, and had heard from folks I trust that the bar was the same design. Someone was nice enough to have posted a picture of a Whiteline bar, in which you can see that the lever arm is not shortened at all. No matter what hole you run, the force still goes straight down into the bar. You don't get more leverage on a pry bar that's bend vs. one that is straight. The lever arm is just not shortened on a Whiteline front bar. Rear bars are very different in that moving the endlink does change the lever arm length of the bar, which is why you see many adjustable rears, and no other adjustable fronts. Everyone else knows the front can't be adjustable with the design Whiteline has.
[/QUOTE]
Once installed it sure appears to me that it would shorten the level arm between the two holes offered. I have not measured it but it appears to be about 3/4" from memory.
I will say this, the thing is damn heavy.
-Paul
| crystalhelix | 01-19-2006 04:47 PM |
[QUOTE=AUTOwrXER]Welcome Sam.
Justin - I'll leave this to you as I left my engineering career at the graduation ceremony. Looks like you're less rusty.[/QUOTE]
I would be borrowing cool "program" resources from work. I just want to impress everyone with fancy pictures.
Justin - I'll leave this to you as I left my engineering career at the graduation ceremony. Looks like you're less rusty.[/QUOTE]
I would be borrowing cool "program" resources from work. I just want to impress everyone with fancy pictures.
| Draken | 01-19-2006 05:21 PM |
Just an FYI, the measurements in post #68 were not just wild guesses for the Whiteline bars. Actual measurements off a bar on my '04 STi. And thinking maybe my head was up my ass, based on Sam's comments that the two-hole position don't change the lever arm, i checked it out again. I went home at lunch, took off my driver side wheel/tire, and measured everything very closely. With actual measuring type implements no less. I made the corresponding calc changes in post #68, as my "lay on my back under the car" method was a tiny bit off. IMO, the "stiff" hole clearly shortens the lever arm, and does effect the bar's stiffness. That's a very simple measurment between two points. In this case, 5.5 and 4.75 inches.
Also, I ran the suspension through a motion of roughly 12" to 14" height (between hub center and fender lip.) In the stiff position, the end link is at or within 5-degrees of vertical during this motion.
And lastly, just to prove that no products are perfect...the end of the Whiteline bar has or is lightly rubbing up against the control arm. Just a hint of scuffing between the two surfaces.
back too hurding turds...
Chris H.
Also, I ran the suspension through a motion of roughly 12" to 14" height (between hub center and fender lip.) In the stiff position, the end link is at or within 5-degrees of vertical during this motion.
And lastly, just to prove that no products are perfect...the end of the Whiteline bar has or is lightly rubbing up against the control arm. Just a hint of scuffing between the two surfaces.
back too hurding turds...
Chris H.
| sstrano | 01-19-2006 07:24 PM |
Let me try again.... You can move the endlink position on the Whiteline bar. That's not what I'm saying. What I'm saying is that no matter where the endlink is positioned the force still goes to the portion of the bar that goes down and around the tie-rod.
Basically you have a "T". The force you get at the bottom of the T is the same whether you are applying pressure to the left or right edge of the top of the T. I don't know how else to explain it. You are not, not, not shortening the length of the lever arm of the bar.
Basically you have a "T". The force you get at the bottom of the T is the same whether you are applying pressure to the left or right edge of the top of the T. I don't know how else to explain it. You are not, not, not shortening the length of the lever arm of the bar.
| Draken | 01-19-2006 07:40 PM |
Sam: Interesting theory
| sciolist | 01-19-2006 08:44 PM |
I think what Sam is saying is that the axis between the centers of the two adjustment holes is nearly perpendicular to the axis of the bar's return arm (hence the "T" term). The two attachment points on the bar result in nearly equal moment arms.
Yes, there is a very small difference, but (judging from the photo above) it's negligible.
Yes, there is a very small difference, but (judging from the photo above) it's negligible.
| D_REX | 01-19-2006 09:20 PM |
Sam,
Are you saying that setting "A" will not be stiffer than setting "B"?
[IMG]http://www.supasubystuff.com/swaybar.JPG[/IMG]
Are you saying that setting "A" will not be stiffer than setting "B"?
[IMG]http://www.supasubystuff.com/swaybar.JPG[/IMG]
| Draken | 01-19-2006 10:19 PM |
Ok...first off...stop laughing. I wanted to prove or disprove the theory Sam mentioned, mostly cause I didn't agree with it and I'm not smart enough to do the math. So, i built a little "device." It is a lever arm with a "T" mounted to it. The lever arm pivots smoothly on the rear footpeg bolt on my 1964 Yamaha YJ1. A 5-pound weight is firmly wired to the other end of the bar. I intended to place weights on the upper arm of the "T" to balance the 5-pound weight out. It operated very smoothly, and the effects of adding small weights did in fact make a noticeable difference. Again, we are talking basic torque here. XX force applied XX distance from the pivot. So here goes:
[COLOR=Red]Longest pivot:[/COLOR]
[img]http://www.subrew.com/tmp/bar_long.jpg[/img]
Required the following mass
-10.75 oz can of Cream of Chicken and Mushroom Soup
-one large fender washers
[COLOR=Red]Middle pivot:[/COLOR]
[img]http://www.subrew.com/tmp/bar_middle.jpg[/img]
Required the following mass
-10.75 oz can of Cream of Chicken and Mushroom Soup
-three large fender washers
-one large M14 nut
[COLOR=Red]Short pivot:[/COLOR]
[img]http://www.subrew.com/tmp/bar_short.jpg[/img]
Required the following mass
-10.75 oz can of Cream of Chicken and Mushroom Soup
-three large fender washers
-two large M14 nuts
-two M12 acorn nuts
-five nickels
-one AA battery
When the "short arm" amount of mass was applied to the "long arm" location, the lever arm easily lifted the 5-pound weight well past centerline, and in fact scared my cat.
So, in very basic terms...the "lever arm" portion of a torsion bar stiffness calculation is the length between the pivot point and the point of the applied force. The shape, length, curveyness of the arm has nothing to do with it, as long as the arm is sufficiently strong enough to not in fact deflect.
And just to show how much it can be affected:
[img]http://www.subrew.com/tmp/bar_extreme.jpg[/img]
Required the following mass
-10.75 oz can of Cream of Chicken and Mushroom Soup
-three large fender washers
-two large M14 nuts
-two M12 acorn nuts
-five nickels
-one AA battery
-one 6 oz can of Bumble Bee tuna (in water)
-one 7.25 oz can of Jenny Craig brand Spinach and Cheese Tortellini (i used to have a fat girlfriend)
So...about what..3 to 4 times the mass than on the "long arm"?
James Bond is on, and I need a beer.
Chris H.
[COLOR=Red]Longest pivot:[/COLOR]
[img]http://www.subrew.com/tmp/bar_long.jpg[/img]
Required the following mass
-10.75 oz can of Cream of Chicken and Mushroom Soup
-one large fender washers
[COLOR=Red]Middle pivot:[/COLOR]
[img]http://www.subrew.com/tmp/bar_middle.jpg[/img]
Required the following mass
-10.75 oz can of Cream of Chicken and Mushroom Soup
-three large fender washers
-one large M14 nut
[COLOR=Red]Short pivot:[/COLOR]
[img]http://www.subrew.com/tmp/bar_short.jpg[/img]
Required the following mass
-10.75 oz can of Cream of Chicken and Mushroom Soup
-three large fender washers
-two large M14 nuts
-two M12 acorn nuts
-five nickels
-one AA battery
When the "short arm" amount of mass was applied to the "long arm" location, the lever arm easily lifted the 5-pound weight well past centerline, and in fact scared my cat.
So, in very basic terms...the "lever arm" portion of a torsion bar stiffness calculation is the length between the pivot point and the point of the applied force. The shape, length, curveyness of the arm has nothing to do with it, as long as the arm is sufficiently strong enough to not in fact deflect.
And just to show how much it can be affected:
[img]http://www.subrew.com/tmp/bar_extreme.jpg[/img]
Required the following mass
-10.75 oz can of Cream of Chicken and Mushroom Soup
-three large fender washers
-two large M14 nuts
-two M12 acorn nuts
-five nickels
-one AA battery
-one 6 oz can of Bumble Bee tuna (in water)
-one 7.25 oz can of Jenny Craig brand Spinach and Cheese Tortellini (i used to have a fat girlfriend)
So...about what..3 to 4 times the mass than on the "long arm"?
James Bond is on, and I need a beer.
Chris H.
| thrdeye | 01-19-2006 10:45 PM |
that's awesome.
| Storm | 01-20-2006 01:37 AM |
Mythbuster in the house!!!!
That's almost as good as the "circle Track" DIY shock dyno. :)
That's almost as good as the "circle Track" DIY shock dyno. :)
| zzyzx | 01-20-2006 02:04 AM |
[QUOTE=Draken]Ok...first off...stop laughing.[/QUOTE]
It took me a while, but I finally did. Awesome <ahem> analysis.
So, the real question: Which would scare your cat more, the Whiteline or Strano bar?
;)
It took me a while, but I finally did. Awesome <ahem> analysis.
So, the real question: Which would scare your cat more, the Whiteline or Strano bar?
;)
| z3coupe | 01-20-2006 04:06 AM |
[QUOTE]FWIW- If you intend to survive in the car hobby past installing blingtastic rims/tires you need to understand that almost nothing in the automotive aftermarket works/fits/looks like OEM. If you need that level fit/finish you should probably stick with stock parts.
-C[/QUOTE][QUOTE]My point still stands unless someone knows an aftermarket company who's every part fits correctly as delivered.....I've never seen one in ~15 years of screwing around with cars.
-C[/QUOTE]Hmmm, just like your tittle, "Scooby Newbie", you really must be one then. I was working in parts & service for Toyota longer than you have been old enough to drive cars. And I was in import car parts for quite some time before that (European Parts Ind, part of Arenco - the FIRST import car parts company in the US, way before BAP-GEON). So you want to talk about screwing around with cars? I used to have to MAKE my own parts for my Truimphs and Lotus's because you simply could not GET them into this country back then, or had to wait half a year before it got shipped here. I had my own Renault R16 parts book so I could get engine parts for my 69 Europa from the Renault dealer - which was 10X faster than getting them from Lotus. And if you ever saw a Renault parts book, it was as hard as reading hieroglyphics!
Now, in THOSE days, it was EXPECTED for parts not to fit right, as it was the dark ages. And concerning Brit sports cars, it was even back to the caveman days. You'd have to go to junk yards to find something that you could modify from another car, to fit on yours. There was no CAD programs, no computer technology to design something. YOU made it. But today, we are in the so called modern technology era. Yes, there can be some minor errors, but that is out of the norm. So am I THAT wrong to expect better than what was back in the pre-CAD days? Expecting better than what Colin Chapman used to design in a backyard garage? Do YOU have the right to trash me for worrying not only about my self, but others as well if this could have become a safety issue? I was wrenching on cars before you were a speck in your daddy's eye kid. I think you owe ME an apology, or I'll deflate the tires on your Big Wheel :devil:
Oh, and what about TRD, Mugen, Nismo, Mazdaspeed, Dinan? Maybe still not 100% perfect (but then neither is 100% of OEM parts either! Just look at Chrysler or Ford as examples), but they now are considered FACTORY parts, and covered under the FACTORY warranty!
Lastly, my wheels are not Blingtastic, nor are they chromed. I came from the days when if it did not go fast, chrome it. I prefer fast.
-C[/QUOTE][QUOTE]My point still stands unless someone knows an aftermarket company who's every part fits correctly as delivered.....I've never seen one in ~15 years of screwing around with cars.
-C[/QUOTE]Hmmm, just like your tittle, "Scooby Newbie", you really must be one then. I was working in parts & service for Toyota longer than you have been old enough to drive cars. And I was in import car parts for quite some time before that (European Parts Ind, part of Arenco - the FIRST import car parts company in the US, way before BAP-GEON). So you want to talk about screwing around with cars? I used to have to MAKE my own parts for my Truimphs and Lotus's because you simply could not GET them into this country back then, or had to wait half a year before it got shipped here. I had my own Renault R16 parts book so I could get engine parts for my 69 Europa from the Renault dealer - which was 10X faster than getting them from Lotus. And if you ever saw a Renault parts book, it was as hard as reading hieroglyphics!
Now, in THOSE days, it was EXPECTED for parts not to fit right, as it was the dark ages. And concerning Brit sports cars, it was even back to the caveman days. You'd have to go to junk yards to find something that you could modify from another car, to fit on yours. There was no CAD programs, no computer technology to design something. YOU made it. But today, we are in the so called modern technology era. Yes, there can be some minor errors, but that is out of the norm. So am I THAT wrong to expect better than what was back in the pre-CAD days? Expecting better than what Colin Chapman used to design in a backyard garage? Do YOU have the right to trash me for worrying not only about my self, but others as well if this could have become a safety issue? I was wrenching on cars before you were a speck in your daddy's eye kid. I think you owe ME an apology, or I'll deflate the tires on your Big Wheel :devil:
Oh, and what about TRD, Mugen, Nismo, Mazdaspeed, Dinan? Maybe still not 100% perfect (but then neither is 100% of OEM parts either! Just look at Chrysler or Ford as examples), but they now are considered FACTORY parts, and covered under the FACTORY warranty!
Lastly, my wheels are not Blingtastic, nor are they chromed. I came from the days when if it did not go fast, chrome it. I prefer fast.
| TheWRX | 01-20-2006 07:32 AM |
That was awesome, Draken. Funniest thing I've seen in quite a while. :lol:
| VpointVick | 01-20-2006 08:02 AM |
[QUOTE=sstrano]Let me try again.... You can move the endlink position on the Whiteline bar. That's not what I'm saying. What I'm saying is that no matter where the endlink is positioned the force still goes to the portion of the bar that goes down and around the tie-rod.
Basically you have a "T". The force you get at the bottom of the T is the same whether you are applying pressure to the left or right edge of the top of the T. I don't know how else to explain it. You are not, not, not shortening the length of the lever arm of the bar.[/QUOTE]
Sorry Sam, but you're wrong on this.
To borrow D_REX's drawing,
[IMG]http://www.supasubystuff.com/swaybar.JPG[/IMG]
the lines marked "A" and "B" are going to be the effective lever arms. It doesn't matter if the actual bar goes down and around the tie rod, so long as the bar rotates around the point prescribed by the bushing, that's where the force is going to be applied.
Basically you have a "T". The force you get at the bottom of the T is the same whether you are applying pressure to the left or right edge of the top of the T. I don't know how else to explain it. You are not, not, not shortening the length of the lever arm of the bar.[/QUOTE]
Sorry Sam, but you're wrong on this.
To borrow D_REX's drawing,
[IMG]http://www.supasubystuff.com/swaybar.JPG[/IMG]
the lines marked "A" and "B" are going to be the effective lever arms. It doesn't matter if the actual bar goes down and around the tie rod, so long as the bar rotates around the point prescribed by the bushing, that's where the force is going to be applied.
| AtomicRacer | 01-20-2006 08:39 AM |
[QUOTE=VpointVick]Sorry Sam, but you're wrong on this.
To borrow D_REX's drawing,
[IMG]http://www.supasubystuff.com/swaybar.JPG[/IMG]
the lines marked "A" and "B" are going to be the effective lever arms. It doesn't matter if the actual bar goes down and around the tie rod, so long as the bar rotates around the point prescribed by the bushing, that's where the force is going to be applied.[/QUOTE]
I believe vector math will support this. That is why I believe it will work. Of course there are two tests that can support this, one is change the setting and drive it (subjective). The other is to measure the force required for a given deflection (objective). I would assume the good people at Adco (sp?)can do the latter.
-Paul
To borrow D_REX's drawing,
[IMG]http://www.supasubystuff.com/swaybar.JPG[/IMG]
the lines marked "A" and "B" are going to be the effective lever arms. It doesn't matter if the actual bar goes down and around the tie rod, so long as the bar rotates around the point prescribed by the bushing, that's where the force is going to be applied.[/QUOTE]
I believe vector math will support this. That is why I believe it will work. Of course there are two tests that can support this, one is change the setting and drive it (subjective). The other is to measure the force required for a given deflection (objective). I would assume the good people at Adco (sp?)can do the latter.
-Paul
| D_REX | 01-20-2006 08:41 AM |
[QUOTE=AtomicRacer]I believe vector math will support this. That is why I believe it will work. Of course there are two tests that can support this, one is change the setting and drive it (subjective). The other is to measure the force required for a given deflection (objective). I would assume the good people at Adco (sp?)can do the latter.
-Paul[/QUOTE]
This is very simple mechanics. If you assume that the connecting member is adequately stiff then it's shape is irrelevant. If it's not adequately stiff then it is a much more complex problem.
-Paul[/QUOTE]
This is very simple mechanics. If you assume that the connecting member is adequately stiff then it's shape is irrelevant. If it's not adequately stiff then it is a much more complex problem.
| VpointVick | 01-20-2006 09:32 AM |
[QUOTE=AtomicRacer]I believe vector math will support this. That is why I believe it will work. Of course there are two tests that can support this, one is change the setting and drive it (subjective). The other is to measure the force required for a given deflection (objective). I would assume the good people at Adco (sp?)can do the latter.
-Paul[/QUOTE]
I think Draken tested this very effectively and most amusingly. :p
-Paul[/QUOTE]
I think Draken tested this very effectively and most amusingly. :p
| sciolist | 01-20-2006 11:55 AM |
[QUOTE=AtomicRacer]I believe vector math will support this. That is why I believe it will work. Of course there are two tests that can support this, one is change the setting and drive it (subjective). The other is to measure the force required for a given deflection (objective). I would assume the good people at Adco (sp?)can do the latter.
-Paul[/QUOTE]
I don't want to split hairs or beat this down any more than it already has been.
D_REX's diagram does not appear to be an accurate representation of what appears in the photo in post #53. It looks to me like the bar in the photo has adjustment holes with an axis more like 70 degrees to the central axis of the lever arm.
Of course any change in lever arm length between the two holes represents a change in stiffness. It just doesn't look like there's much change in length in the configuration shown in the photo.
That's the only representation I've ever seen of the end of a Whiteline adjustable FSB, so maybe I'm just not interpreting the photo correctly.
-Paul[/QUOTE]
I don't want to split hairs or beat this down any more than it already has been.
D_REX's diagram does not appear to be an accurate representation of what appears in the photo in post #53. It looks to me like the bar in the photo has adjustment holes with an axis more like 70 degrees to the central axis of the lever arm.
Of course any change in lever arm length between the two holes represents a change in stiffness. It just doesn't look like there's much change in length in the configuration shown in the photo.
That's the only representation I've ever seen of the end of a Whiteline adjustable FSB, so maybe I'm just not interpreting the photo correctly.
| BrianGT | 01-20-2006 12:00 PM |
Here are a few more pics of the whiteline bar before I installed it on my car:
[img]http://mere.darg.net/albums/s2k-victoracers/s2k_upg_002.sized.jpg[/img]
[img]http://mere.darg.net/albums/s2k-victoracers/s2k_upg_003.sized.jpg[/img]
[img]http://mere.darg.net/albums/s2k-victoracers/s2k_upg_004.sized.jpg[/img]
Hope they help a bit. Bar next to is a 1.25" solid bar that I had in my old s2k.
--
Brian
[img]http://mere.darg.net/albums/s2k-victoracers/s2k_upg_002.sized.jpg[/img]
[img]http://mere.darg.net/albums/s2k-victoracers/s2k_upg_003.sized.jpg[/img]
[img]http://mere.darg.net/albums/s2k-victoracers/s2k_upg_004.sized.jpg[/img]
Hope they help a bit. Bar next to is a 1.25" solid bar that I had in my old s2k.
--
Brian
| PossumK | 01-20-2006 01:09 PM |
[QUOTE=sciolist]Of course any change in lever arm length between the two holes represents a change in stiffness. It just doesn't look like there's much change in length in the configuration shown in the photo.
That's the only representation I've ever seen of the end of a Whiteline adjustable FSB, so maybe I'm just not interpreting the photo correctly.[/QUOTE]
Refer to post #92. Draken made the physical measurements, rather than going by a photo:
[url]http://forums.nasioc.com/forums/showpost.php?p=12369454&postcount=92[/url]
That's the only representation I've ever seen of the end of a Whiteline adjustable FSB, so maybe I'm just not interpreting the photo correctly.[/QUOTE]
Refer to post #92. Draken made the physical measurements, rather than going by a photo:
[url]http://forums.nasioc.com/forums/showpost.php?p=12369454&postcount=92[/url]
| sciolist | 01-20-2006 01:10 PM |
Okay, and that last photo is a pretty good illustration of what Sam's talking about. On the Whiteline bar, the two bolt-up holes are positioned on an axis that's very nearly perpendicular to the bar's lever arm (Sam's "T"). On the the S2K bar, the holes are essentially parallel to the bar's lever arm.
On the Whiteline bar, you're making almost no change in the effective moment arm by changing holes. On the S2K bar, you are changing the moment arm.
On the Whiteline bar, you're making almost no change in the effective moment arm by changing holes. On the S2K bar, you are changing the moment arm.
| D_REX | 01-20-2006 01:14 PM |
[QUOTE=sciolist]Okay, and that last photo is a pretty good illustration of what Sam's talking about. On the Whiteline bar, the two bolt-up holes are positioned on an axis that's very nearly perpendicular to the bar's lever arm (Sam's "T"). On the the S2K bar, the holes are essentially parallel to the bar's lever arm.
On the Whiteline bar, you're making almost no change in the effective moment arm by changing holes. On the S2K bar, you are changing the moment arm.[/QUOTE]
Are you accusing Draken of lying or questioning his measuring abilities?
He says that he MEASURED the two distances as 0.75" different.
On the Whiteline bar, you're making almost no change in the effective moment arm by changing holes. On the S2K bar, you are changing the moment arm.[/QUOTE]
Are you accusing Draken of lying or questioning his measuring abilities?
He says that he MEASURED the two distances as 0.75" different.
| PossumK | 01-20-2006 01:18 PM |
It looks, in the photo you're referencing, like the 0.75" that Draken measured. The S2000's holes don't appear to change the moment arm much more than that.
| AtomicRacer | 01-20-2006 01:20 PM |
[QUOTE=sciolist]Okay, and that last photo is a pretty good illustration of what Sam's talking about. On the Whiteline bar, the two bolt-up holes are positioned on an axis that's very nearly perpendicular to the bar's lever arm (Sam's "T"). On the the S2K bar, the holes are essentially parallel to the bar's lever arm.
On the Whiteline bar, you're making almost no change in the effective moment arm by changing holes. On the S2K bar, you are changing the moment arm.[/QUOTE]
[img]http://memimage.cardomain.net/member_images/11/web/2075000-2075999/2075362_19_full.jpg[/img]
Look at the above picture of the whiteline bar installed. Notice that the holes do in fact shorten the lever arm. Now that we all understand how this works (and it does work), please stop saying it doesn't and let's move back to our regular programming.
-Paul
On the Whiteline bar, you're making almost no change in the effective moment arm by changing holes. On the S2K bar, you are changing the moment arm.[/QUOTE]
[img]http://memimage.cardomain.net/member_images/11/web/2075000-2075999/2075362_19_full.jpg[/img]
Look at the above picture of the whiteline bar installed. Notice that the holes do in fact shorten the lever arm. Now that we all understand how this works (and it does work), please stop saying it doesn't and let's move back to our regular programming.
-Paul
| sciolist | 01-20-2006 01:32 PM |
[QUOTE=D_REX]Are you accusing Draken of lying or questioning his measuring abilities?
He says that he MEASURED the two distances as 0.75" different.[/QUOTE]
Absolutely not. I'm simply trying to shed some light on what I think Sam meant when he made the statement about the "T" configuration.
I understand perfectly well that the difference in leverage is a function of the different lengths of the lever arms, and I have no reason to believe Draken can't measure. I can however, see how someone might look at a photo of the Whiteline bar and reach the conclusion that it has only negligible adjustability.
He says that he MEASURED the two distances as 0.75" different.[/QUOTE]
Absolutely not. I'm simply trying to shed some light on what I think Sam meant when he made the statement about the "T" configuration.
I understand perfectly well that the difference in leverage is a function of the different lengths of the lever arms, and I have no reason to believe Draken can't measure. I can however, see how someone might look at a photo of the Whiteline bar and reach the conclusion that it has only negligible adjustability.
| D_REX | 01-20-2006 01:35 PM |
[QUOTE=sciolist]Absolutely not. I'm simply trying to shed some light on what I think Sam meant when he made the statement about the "T" configuration.
I understand perfectly well that the difference in leverage is a function of the different lengths of the lever arms, and I have no reason to believe Draken can't measure. I can however, see how someone might look at a photo of the Whiteline bar and reach the conclusion that it has only negligible adjustability.[/QUOTE]
Ahhh, I misunderstood. Yes, I agree, from many angles the whiteline bar looks like the range of adjustment may be innefective.
I understand perfectly well that the difference in leverage is a function of the different lengths of the lever arms, and I have no reason to believe Draken can't measure. I can however, see how someone might look at a photo of the Whiteline bar and reach the conclusion that it has only negligible adjustability.[/QUOTE]
Ahhh, I misunderstood. Yes, I agree, from many angles the whiteline bar looks like the range of adjustment may be innefective.
| Draken | 01-20-2006 02:21 PM |
I agree it looks weird from many angles. And Sam's comments did make me wonder, hence my tuna can experiement. And yes, 3/4" is not much of a change...except when you only have around 5-inches to begin with. And i feel good about my measurments, however, they were made while the bar was on the car, so if i'm off a little on any or all, we could be talking about a +-10% stiffness change.
Also, please note the numbers for the Strano bar are pure guesses on my part, based on photos. Noone has actually provided any measured values for the lever arm and mid-section of the bar. These numbers too could change 10% plus or minus.
Chris H.
Also, please note the numbers for the Strano bar are pure guesses on my part, based on photos. Noone has actually provided any measured values for the lever arm and mid-section of the bar. These numbers too could change 10% plus or minus.
Chris H.
| crystalhelix | 01-20-2006 02:57 PM |
It looks like the whiteline bar really snakes down in size towards then end though. You know the saying "the weakest link", what's going on with that? What does the thick section measure and what does it taper down to for forming the end geometry.
Justin
Justin
| sstrano | 01-20-2006 04:57 PM |
The experiment run on the moped is very different. There is a lever, look at where the (I can't believe I'm saying this) is placed vs. the down tube. That distance is a lever arm, and it's length is being changed. However, as can easily be seen on the pics of Whiteline bar, the holes are both almost right on top of the down tube.
Further, it'd help if the bars off the different cars were oriented properly. The S2000 bar is certainly adjustable because as move the link up the arm, you shorten the lever. That's just not the case on the Subaru bar.
If the Honda bar was like this
---------------0
0 0 0 |
---------------0
And each 0 was a hole.... The 3 holes that change the length of the bar change the stiffness of the bar. The 2 hole that are stacked on the end, are the same. Softer than the other 3, but no different than each other because neither changes the length of the lever arm.
Here is "drawing" of the Subaru setup.
----------
| 0 0 |
|.........|
|.......|
|.......|
Neither hole can change the leverage applied to the bar because there is no LEVER ARM to change. In this case, if the adjustment holes were stacked on top of each other, then the bottom one would slightly strengthen the bar because you'd simply have less linear length of material flexing. But this orientation does not lessen the amount of metal that's flexing.
I hope to high heaven someone builds a jig and tries it.
Now, I'll concede with the way the bar is on the car that you might see a *SLIGHT* change in bar rate given the bar does not drop straight down from the endlink.
HOWEVER, and this is what the point is and was.... IT IS NOT ANYWHERE NEAR ENOUGH OF A CHANGE TO MAKE THE 27mm BAR ACT AS A 29MM BAR!!!!
Further, it'd help if the bars off the different cars were oriented properly. The S2000 bar is certainly adjustable because as move the link up the arm, you shorten the lever. That's just not the case on the Subaru bar.
If the Honda bar was like this
---------------0
0 0 0 |
---------------0
And each 0 was a hole.... The 3 holes that change the length of the bar change the stiffness of the bar. The 2 hole that are stacked on the end, are the same. Softer than the other 3, but no different than each other because neither changes the length of the lever arm.
Here is "drawing" of the Subaru setup.
----------
| 0 0 |
|.........|
|.......|
|.......|
Neither hole can change the leverage applied to the bar because there is no LEVER ARM to change. In this case, if the adjustment holes were stacked on top of each other, then the bottom one would slightly strengthen the bar because you'd simply have less linear length of material flexing. But this orientation does not lessen the amount of metal that's flexing.
I hope to high heaven someone builds a jig and tries it.
Now, I'll concede with the way the bar is on the car that you might see a *SLIGHT* change in bar rate given the bar does not drop straight down from the endlink.
HOWEVER, and this is what the point is and was.... IT IS NOT ANYWHERE NEAR ENOUGH OF A CHANGE TO MAKE THE 27mm BAR ACT AS A 29MM BAR!!!!
| VpointVick | 01-20-2006 05:20 PM |
Sam,
if the bar goes
-------------------
[-o--o------------P
-------------------
and the "o"s represent the endlink holes, and the "P" represents the pivot, it adjusts the lever arm, no?
Well, if the bar goes
..l-o-o-l.................lP l
...l----l..................l--l
...\----\................/-/
....\----\............../-/
......\--------------/
.......\___________/
it's exactly the same as long as the pickup points are equal. The [I]shape[/I] of the bar has no bearing. All that matters is where the endlinks pick up in relation to the pivot point at the bushing.
Changing holes on illustration #2 will change the lever arm length every bit as much as illustration #1. Barring flex in the bent arm, pivot to pick up point distance is all that matters.
if the bar goes
-------------------
[-o--o------------P
-------------------
and the "o"s represent the endlink holes, and the "P" represents the pivot, it adjusts the lever arm, no?
Well, if the bar goes
..l-o-o-l.................lP l
...l----l..................l--l
...\----\................/-/
....\----\............../-/
......\--------------/
.......\___________/
it's exactly the same as long as the pickup points are equal. The [I]shape[/I] of the bar has no bearing. All that matters is where the endlinks pick up in relation to the pivot point at the bushing.
Changing holes on illustration #2 will change the lever arm length every bit as much as illustration #1. Barring flex in the bent arm, pivot to pick up point distance is all that matters.
| Draken | 01-20-2006 05:33 PM |
[QUOTE=sstrano]The experiment run on the moped is very different.[/QUOTE]
IT'S NOT A MOPED DAMN IT!!!!
Per the claim the change in hole position does not give the stiffness of a 29mm bar: You are right. The whiteline bar run on the "stiff" hole position has an effective spring rate of 1,731.9 lbs/in. based on my feeble calcs.
It's the equivalent of a 28.97mm bar on the "soft hole." Not quite 29mm.
Chris H.
IT'S NOT A MOPED DAMN IT!!!!
Per the claim the change in hole position does not give the stiffness of a 29mm bar: You are right. The whiteline bar run on the "stiff" hole position has an effective spring rate of 1,731.9 lbs/in. based on my feeble calcs.
It's the equivalent of a 28.97mm bar on the "soft hole." Not quite 29mm.
Chris H.
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