Thứ Sáu, 30 tháng 12, 2016

What is the best autocross mod? part 1

ATXWRX 09-08-2006 10:08 PM

What is the best autocross mod?
Other than tires.
nater 09-08-2006 10:09 PM

sway bars
waktasz 09-08-2006 10:10 PM

Driving school.
solo2wrx 09-08-2006 10:12 PM

[QUOTE=waktasz;15181578]Driving school.[/QUOTE]

+1 An Evolution school is very good for any autocrosser.
Protege Menace 09-08-2006 10:13 PM

practice.
Dan00RS 09-08-2006 10:23 PM

Fixing the loose nut behind the wheel.
speedyHAM 09-08-2006 10:31 PM

[QUOTE=Dan00RS;15181647]Fixing the loose nut behind the wheel.[/QUOTE]

Translation- Driving school.

As far as physical mods- tires (obviously), Front sway bar for stock class. For STX you are going to need a lot more than sway bars to be competitive.
bl_easy 09-08-2006 11:13 PM

My favourite so far (after tires) - harness.

Do it.

... I haven't had a chance to get to a driving school yet. :(
Mykl 09-09-2006 01:38 AM

Swaybars.
soldmyboxster 09-09-2006 01:41 AM

Another vote here for the driving school. It will make you realize just how crappy of a driver you were before you took the class.
rallymaniac 09-09-2006 01:42 AM

[QUOTE=speedyHAM;15181696]
Front sway bar for stock class. [/QUOTE]
??? so you can understeer more??? :huh:
Just do the right suspension change with proper alignment.
Mykl 09-09-2006 01:45 AM

I didn't like the way my car handled with just an upgraded front swaybar, at least not for autocrossing. For the track it felt fine, although it necessitated that I not overdrive the car at turn in at all.
chimchimm5 09-09-2006 01:53 AM

Everyone beat me.

"the driver"
waktasz 09-09-2006 02:00 AM

[QUOTE=rallymaniac;15182947]??? so you can understeer more??? :huh:
Just do the right suspension change with proper alignment.[/QUOTE]

No, so the front stays flatter and you get more traction in the front, which will make you understeer less.
Impreza01 09-09-2006 02:10 AM

[QUOTE=waktasz;15183017]No, so the front stays flatter and you get more traction in the front, which will make you understeer less.[/QUOTE]

Not entirely true. The front sway bar till give you better turn-in because it increases the limit of the front's grip. However, once surpassing the limit, you will understeer.
chimchimm5 09-09-2006 02:18 AM

[QUOTE=Impreza01;15183067]Not entirely true. The front sway bar till give you better turn-in because it increases the limit of the front's grip. However, once surpassing the limit, you will understeer.[/QUOTE]

Yes, but isn't that what "understeer less" is?

"understeer less" does not equal "oversteer more"
Mykl 09-09-2006 02:40 AM

[QUOTE=chimchimm5;15183102]Yes, but isn't that what "understeer less" is?

"understeer less" does not equal "oversteer more"[/QUOTE]

I guess it depends on how you look at it. At 8/10's or 9/10's the car feels great, but when you hit 10/10's it gets really tricky, it's like you're dancing on the magical understeer line, and if you cross it the understeer is horrid. What makes it worse is that the line is vague and a bit difficult to read.

The car understeers like it did to begin with, it just does it at a slightly higher grip level due to the more favorable camber curve.

If your technique is slow-in-fast-out then just upgrading the front swaybar is good. But if you like driving a car where the front and rear traction breaks loose at closer to the same time, you won't like it at all.

Personally, I like the feel of an evenly matched pair of swaybars, maybe with the rear a tad more powerful than the front. I may not have as much grip as the guy running a monster swaybar up front, but I find that my car is easier to read at the limit.




However... if you're bound to stock class rules you may be able to even up the grip between the front and rear by playing with the toe settings. That could reduce some of the harshness of the understeer that sets in with a big-ass front bar.
DrBiggly 09-09-2006 10:49 AM

[QUOTE=Mykl;15183227]...The car understeers like it did to begin with, it just does it at a slightly higher grip level due to the more favorable camber curve.

[/QUOTE]

Bingo! Most folks take forever to figure this concept out or never manage at all. What folks forget about the 'front bar only' upgrade for autox is that it both reduces "understeer" but makes it "understeer" more. :huh:

It reduces understeer in the sense of the car refusing to turn any longer at a particular speed; speeds are higher as grip is higher due to the better camber curve afforded by the larger bar. It adds understeer in the sense the car will push a little worse than it did before once one has passed the limit of grip.

Like you mentioned, it's a tricky line to walk and lots of folks find it difficult to do. The fast autocrossers are always faster with the bigger front bar because they have the experience to manage grip on the limit properly rather than passing the limit constantly and being unable to figure it out.

So when someone asks "Does the bigger front bar make the car understeer less" the proper answer is both yes and no. :)

edit: Got off topic there. Really the best modification is the driver. Physical modifications are tires first then finding the best way to extract grip and balance the feel of the car beyond that.

-Biggly
Evil STI 09-09-2006 11:16 AM

[QUOTE=Dan00RS;15181647]Fixing the loose nut behind the wheel.[/QUOTE]

^Yes.
timmyp 09-09-2006 11:26 AM

[quote=DrBiggly;15184419]Bingo! Most folks take forever to figure this concept out or never manage at all. What folks forget about the 'front bar only' upgrade for autox is that it both reduces "understeer" but makes it "understeer" more. :huh:

It reduces understeer in the sense of the car refusing to turn any longer at a particular speed; speeds are higher as grip is higher due to the better camber curve afforded by the larger bar. It adds understeer in the sense the car will push a little worse than it did before once one has passed the limit of grip.

Like you mentioned, it's a tricky line to walk and lots of folks find it difficult to do. The fast autocrossers are always faster with the bigger front bar because they have the experience to manage grip on the limit properly rather than passing the limit constantly and being unable to figure it out.

So when someone asks "Does the bigger front bar make the car understeer less" the proper answer is both yes and no. :)

-Biggly[/quote]



Sorry to butt in, but a front swaybar doesn't [I]improve[/I] the camber curve, it just limits it's movement
pleiades 09-09-2006 12:22 PM

[QUOTE=timmyp;15184585]Sorry to butt in, but a front swaybar doesn't [I]improve[/I] the camber curve, it just limits it's movement[/QUOTE]


I love it when someone takes the time to type out a long post and explain something for the benefit of others, then some n00b comes along and tells them they are wrong, without taking the time to actually explain why they are wrong. So, do you have the info to back up your statement or are you just saying you're right and we should listen to you becuase you've posted about Subarus or something a whole 21 times on this board.

I'm not saying you're right or wrong, because I don't have the facts to back up either argument. You just need to understand that when you make a statement without explaining why then you are not doing jack **** for anyone. Thanks!
shikataganai 09-09-2006 01:58 PM

pleiades:

1. a swaybar reduces independent movement of the wheels while cornering
2. the camber curve refers to how the camber changes over a wheel's travel
3. a swaybar does not affect how the camber changes over a wheel's travel

from 1 and 3 we see that a swaybar does not change (or improve) the camber curve. from 1 and 2 we see that the wheel will be moving less, presumably with less change in camber due to this (assuming there's not a huge change in camber near the point in the wheel's travel that we're examining).

back to the OP's question: driving school, evolution school, and then tires.
Mykl 09-09-2006 02:11 PM

[QUOTE=timmyp;15184585]Sorry to butt in, but a front swaybar doesn't [I]improve[/I] the camber curve, it just limits it's movement[/QUOTE]

You're right, please excuse my poor choice of words.
DrBiggly 09-09-2006 02:24 PM

[QUOTE=timmyp;15184585]Sorry to butt in, but a front swaybar doesn't [I]improve[/I] the camber curve, it just limits it's movement[/QUOTE]

Not quite; the camber curve is a static factor and does not move per se. To be more specific: A larger front bar limits the wheel's change in camber via reducing bodyroll and thus limiting how far along the camber curve the loaded wheel in question can travel. Is it an improvement in the fundamental camber curve itself? No, you need the 6Gun Racing Balljoint Extension Kit for that. But it does improve the vehicle in question's camber curve as related only to the contact patch itself (of course via a reduction in bodyroll.) :)

-Biggly
Uber Wagon 09-09-2006 02:45 PM

Besides driving school, I think a proper alignment is the best performance mod...
Impreza01 09-09-2006 06:15 PM

[QUOTE=chimchimm5;15183102]Yes, but isn't that what "understeer less" is?

"understeer less" does not equal "oversteer more"[/QUOTE]


[QUOTE=DrBiggly;15184419]Bingo! Most folks take forever to figure this concept out or never manage at all. What folks forget about the 'front bar only' upgrade for autox is that it both reduces "understeer" but makes it "understeer" more. :huh:
-Biggly[/QUOTE]

There's your answer chimchimm5. It's not a matter of semantics, but it's the fact that the car will understeer more once you pass the limit. When you're under the limit of a car's grip, you can't really say a car is understeering or oversteering since the slip angle of the car is following the steering wheel.

OP: Improve Driver -> tires -> alignment -> swaybars -> coilovers -> alignment.
Calamity Jesus 09-10-2006 07:56 AM

[QUOTE=DrBiggly;15185703]Not quite; the camber curve is a static factor and does not move per se. To be more specific: A larger front bar limits the wheel's change in camber via reducing bodyroll and thus limiting how far along the camber curve the loaded wheel in question can travel. Is it an improvement in the fundamental camber curve itself? No, you need the 6Gun Racing Balljoint Extension Kit for that. But it does improve the vehicle in question's camber curve as related only to the contact patch itself (of course via a reduction in bodyroll.) :)

-Biggly[/QUOTE]
In other words.. it depends entirely upon which 'other' factor you're talking about when you mention the camber curve. If you graph suspension travel vs camber, it will remain the same. If you graph lateral G vs camber, the curve (amount of change) will be smaller.


Feel free to butt in anytime shika, but always beware the semantics discussion that will follow :devil:
JnJassociates 09-10-2006 08:38 AM

As a vendor, it would be in my best interest to tell you to buy sway bars and the like... ;)

However, the best thing you can do to improve your times is practice. Get as much seat time. If you have the opportunity to attend an Evolution school. Do it! From just stage one of the autocross school, I was able to improve my times dramatically.

Here is a link: [url]http://autocross.server269.com/evolution/modules/news/[/url]

Also, have some of the more experienced or if you are luck enough to have some National drivers in your club, ride with you. They can give you valuable feedback.


Bryan
makofoto 09-10-2006 09:27 AM

+1 for having a top driver drive you around in your car, so you can see what's possible. Gives you a lot of confidence in your car ...
shikataganai 09-10-2006 02:04 PM

[QUOTE=Beaverboy;15191238]In other words.. it depends entirely upon which 'other' factor you're talking about when you mention the camber curve. If you graph suspension travel vs camber, it will remain the same. [B]If you graph lateral G vs camber, the curve (amount of change) will be smaller[/B].

Feel free to butt in anytime shika, but always beware the semantics discussion that will follow :devil:[/QUOTE]
if you graph lateral acceleration vs. camber then you could argue that stiffer springs "improve the camber curve." doesn't that sound ridiculous? anyway, i've already made my point in this thread. :D
Kostamojen 09-10-2006 03:00 PM

Adjustable suspension
Butt Dyno 09-10-2006 06:55 PM

Driver > tires > alignment (camber bolts?) > other stuff
Fogrider 09-10-2006 07:05 PM

best mod= train/improve driver (schools, practice,read,watch; however you best learn.)
Calamity Jesus 09-10-2006 09:01 PM

[QUOTE=shikataganai;15192964]if you graph lateral acceleration vs. camber then you could argue that stiffer springs "improve the camber curve." doesn't that sound ridiculous?[/QUOTE]Not at all. Half the reason stiff springs are used on track cars is because the alignment changes less as weight transfers... the other half is quicker weight transfer, but that doesn't do much to help on a flowing track.

The point is, this forum is full of people who will never go to great lengths to modify their suspension design in order to actually change the camber curve (vs travel ;)). It's easier to explain to a n0ob that swaybars and springs will help to limit camber changes which are detrimental to an Impreza's roadholding ability. So the terminology we use isn't 100% accurate.. only the engineers will care.:p
WRX-ECE 09-10-2006 10:26 PM

[QUOTE=pleiades;15184890]I love it when someone takes the time to type out a long post and explain something for the benefit of others, then some n00b comes along and tells them they are wrong, without taking the time to actually explain why they are wrong. So, do you have the info to back up your statement or are you just saying you're right and we should listen to you because you've posted about Subarus or something a whole 21 times on this board.

I'm not saying you're right or wrong, because I don't have the facts to back up either argument. You just need to understand that when you make a statement without explaining why then you are not doing jack **** for anyone. Thanks![/QUOTE]

I love it when someone acts like an asshat and posts something like this, thinking that pointing out he has 21 posts on NASIOC will somehow invalidate his very correct statement... cause you know, if your member number isn't below 2500 then you are a looser n00b who, blah blah blah, maybe you are frustrated because you can't understand the simple geometry that makes his point correct and need him to explain more so you understand...

But back on topic, driver, driver driver... then driver. I can attest to this, I went to coil-overs too early and did a bunch of other crap and it put my driving back years, cause when I reached the limits of my cars setup I didn't have the background to attack the problem properly, had I spent more time learning the car then I could have progressed faster overall...

But what do I know, I haven't autocrossed a Subaru in over a year

Jeremy
AndyRoo 09-10-2006 11:39 PM

[QUOTE=ButtDyno;15195022]Driver > tires > alignment (camber bolts?) > other stuff[/QUOTE]

+1 for tires and alignment before other stuff.


- drew
Calamity Jesus 09-11-2006 01:47 PM

[QUOTE=WRX-ECE;15197011]maybe you are frustrated because you can't understand the simple geometry that makes his point correct and need him to explain more so you understand...[/QUOTE]
I don't think Mr. Rankins has any trouble understanding the geometry.. ..as we've already discussed, it was more an issue of terminology. Either way, he was just saying that a little more explanation was due... :huh:
WRX-ECE 09-11-2006 03:00 PM

[QUOTE=Beaverboy;15203545]I don't think Mr. Rankins has any trouble understanding the geometry.. ..as we've already discussed, it was more an issue of terminology. Either way, he was just saying that a little more explanation was due... :huh:[/QUOTE]

My response = PM sent since this is now way off topic.
KC 09-11-2006 03:22 PM

Has anyone said driver yet? Just want to be sure that this thread didn't go by without anyone saying it.
DrBiggly 09-11-2006 03:29 PM

[QUOTE=KC;15204933]Has anyone said driver yet? Just want to be sure that this thread didn't go by without anyone saying it.[/QUOTE]

Nope, you're the first I think. :alien: :p

-Biggly
Templar 09-11-2006 03:43 PM

[QUOTE=WRX-ECE;15197011]... cause you know, if your member number isn't below 2500 then you are a looser n00b [/QUOTE]



Truer words have never been spoken...or typed. ;)
Bacon117 09-11-2006 03:45 PM

Better Tires!!
InfiniteMotorsports 09-11-2006 03:47 PM

1st- learn to drive
2nd- weight reduction
3rd- all others in order of importance
sachilles 09-11-2006 05:20 PM

driver education first
Otherwise tires and alignments are wasted.
Next up is seat time...practice makes perfect.
I also think a video camera is a good investment to see objectively what you are doing while on the course....but that falls under driver education.
Funky 09-11-2006 06:44 PM

[QUOTE=DrBiggly;15205040]Nope, you're the first I think. :alien: :p

-Biggly[/QUOTE]

Heh, well. In that case I'll be the 2nd to say "driver".

Get all the seat time you can, if you have some really good drivers (read: national champions) in your region have them ride with you. Ride with them, really listen to what they say. They know.

Drive more events, try to incorporate the things they tell you. Rinse, repeat.
racerx321 09-11-2006 08:05 PM

CG Lock is another nice (and low cost!) improvement. Not sure there's much objective data, but it does seem to free that portion of your unconscious that's otherwise working to hold you in your seat.
ATXWRX 09-12-2006 10:13 AM

Cool thanks for all the advice. It sounds like I'm on the right track then. I just need more seat time!
ratt_finkel 09-12-2006 11:55 AM

Stickers, and a big exhaust tip.
Student Driver 09-12-2006 12:14 PM

[QUOTE=ratt_finkel;15216296]Stickers, and a big exhaust tip.[/QUOTE]


He's right. Get rid of those things and you'll be t3h f4stAr in no time...

;)
Bacon117 09-12-2006 01:43 PM

[QUOTE=ratt_finkel;15216296]Stickers, and a big exhaust tip.[/QUOTE]

no no no, underbody light kits are the way to go! The photons of light help move the air under the car faster, creating downforce!!! :rolleyes:
Mykl 09-12-2006 02:01 PM

For counter points on the swaybar discussion, read here...

[url]http://forums.nasioc.com/forums/showthread.php?t=1008667[/url]
Butt Dyno 09-12-2006 02:17 PM

[QUOTE=Mykl;15218370]For counter points on the swaybar discussion, read here...

[url]http://forums.nasioc.com/forums/showthread.php?t=1008667[/url][/QUOTE]

I wouldn't call it a counter point, more like a discussion :)

I still think the big front bar is one of the best suspension mods I've done. It just takes some getting used to.

john
STFU STi 09-13-2006 09:38 AM

beating a dead-horse
Seat-time
Alignment.
street tires (hankook or Falken or RE070's)

after a season or two then worry about the other stuff.



I still don't consider myself a good driver, but I am glad I invested money in attending the 30 or so autoXs this season instead of coil-overs, exhaust, accessport, sway-bars, lighter wheels, etc... and only run 5 events...

when i get good enough for that stuff, then I'll re-weight the benefits.

Không có nhận xét nào:

Đăng nhận xét