| teamipr | 10-27-2003 02:56 PM |
STi Track Experience/Review and Questions
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I had my first STi track event last Saturday at Sear Point (Infineon Racewa). I've had a lot of track experience before but all in RWD cars, N/A SW20 MR2 and E36 M3, and I've driven both at SP before. I have to say I'm a bit dissapointed with the STi. Maybe I'm expecting too much from the car, or that I just don't know how to drive a AWD car. But, please read on and if you have experiences in the Sti on track, please give some feedback and answers to my review.
Power: no complaints here. The power is great to redline and lots of low end torque. I can come out of T4 in 4th gear at 3 K RPM and pull nicely to T6.
Handling: Major complaint is there's A LOT of body roll. It feels like the car is just about to go 2 wheels off through the apex. The steering still fells a bit vague even after changing the steering rack bushings. My E36 M3 felt more planted through the corners, maybe it's heavier, and I can carry more speed through the corners. I didn't feel as confident in the STi as I did in the M3. And I'm not use to the pulling of the car at the exit of corners. The car pushes at the exit as I get on the gas and then the front diff binds and pulls the car. A bid weird feeling...I'm not used to that.
Tires: I think the Petenza 070s are crappy track tires. And I think they contribute to the handling faults. They were barking like hell in every corner. I had the pressure set at 31 front and 30 rear cold. They felt like they just wanted to slide.
Brakes: GREAT! But the peddel position is not heel-toe friendly. The peddel went down much lower than the gas and this made heel-toe hard to do. I think double clutch would be better here, I need to learn that now.
Overall: Othere than the weird handling and crappy tires I thougt the STi is a great all around car but not very suited for the track unless things are changed. The toothpick thin sway bars need to be changed to thicker ones.
Please help and give me some input on how to drive the car better. I know I can drive it faster even in its current stock form. My friend timed me at a fastest time of 2:09 but I did a 2:08 with my M3 before. I'll be going back again in Nov, I hope I can do better then.
Will
Power: no complaints here. The power is great to redline and lots of low end torque. I can come out of T4 in 4th gear at 3 K RPM and pull nicely to T6.
Handling: Major complaint is there's A LOT of body roll. It feels like the car is just about to go 2 wheels off through the apex. The steering still fells a bit vague even after changing the steering rack bushings. My E36 M3 felt more planted through the corners, maybe it's heavier, and I can carry more speed through the corners. I didn't feel as confident in the STi as I did in the M3. And I'm not use to the pulling of the car at the exit of corners. The car pushes at the exit as I get on the gas and then the front diff binds and pulls the car. A bid weird feeling...I'm not used to that.
Tires: I think the Petenza 070s are crappy track tires. And I think they contribute to the handling faults. They were barking like hell in every corner. I had the pressure set at 31 front and 30 rear cold. They felt like they just wanted to slide.
Brakes: GREAT! But the peddel position is not heel-toe friendly. The peddel went down much lower than the gas and this made heel-toe hard to do. I think double clutch would be better here, I need to learn that now.
Overall: Othere than the weird handling and crappy tires I thougt the STi is a great all around car but not very suited for the track unless things are changed. The toothpick thin sway bars need to be changed to thicker ones.
Please help and give me some input on how to drive the car better. I know I can drive it faster even in its current stock form. My friend timed me at a fastest time of 2:09 but I did a 2:08 with my M3 before. I'll be going back again in Nov, I hope I can do better then.
Will
| afpdl | 10-27-2003 03:39 PM |
Put some more air in the tires, you had to be chewing up your sidewalls at 30psi. You should be running higher then stock pressure or at least stock pressure but definetly not lower.
And the Sti is going to have more body roll then your old m3 unless you spring the hell out of it, swaybars will reduce roll but they will also reduce ultimate grip. What feels faster isnt always faster.
And the Sti is going to have more body roll then your old m3 unless you spring the hell out of it, swaybars will reduce roll but they will also reduce ultimate grip. What feels faster isnt always faster.
| ANZAC_1915 | 10-27-2003 03:47 PM |
[quote] I had the pressure set at 31 front [/quote]
The recommended front pressure for road use is 36 PSI. I would have started at least there, if not 2 PSI higher.
As you get more aggressive with the car the front diff will pull earlier and you get less of a weird feeling.
Glenn
The recommended front pressure for road use is 36 PSI. I would have started at least there, if not 2 PSI higher.
As you get more aggressive with the car the front diff will pull earlier and you get less of a weird feeling.
Glenn
| ChrisW | 10-27-2003 04:11 PM |
[QUOTE][i]Originally posted by Glenn Wallace [/i]
[B]The recommended front pressure for road use is 36 PSI. I would have started at least there, if not 2 PSI higher.
As you get more aggressive with the car the front diff will pull earlier and you get less of a weird feeling.
Glenn [/B][/QUOTE]
guess I need to check my presures as well.
Like Glenn said, you can be more aggresive than with your typical RWD car.
[B]The recommended front pressure for road use is 36 PSI. I would have started at least there, if not 2 PSI higher.
As you get more aggressive with the car the front diff will pull earlier and you get less of a weird feeling.
Glenn [/B][/QUOTE]
guess I need to check my presures as well.
Like Glenn said, you can be more aggresive than with your typical RWD car.
| HoRo1 | 10-27-2003 04:17 PM |
Sounds EXACTLY like the handling on my WRX except with 30% more power.
For street and track rubber run Azenis. They are fairly inexpensive but grip very well (and can wear quickly). 40lbs hot is a reasonable benchmark for tyres at the track. Start there and adjust accordingly.
Body roll is nasty on WRXs and Stis. I'm sure that you'll work out something with sway bars/springs whatever.
Get used to the understeer. You'll be able to dial some of it out. Stiffen up the rear end and run a lot of negative camber at the front and it will help. I run DMS50s and still have boatloads of understeer in long sweepers. If you think you're getting a lot of understeer at Sears, try turn 2 at Willow! I kill people in turn 1 but when we get to turn 2, they either form a queue behind me or overtake on the [B]outside[/B]. So frustrating!
I think that you might need a new brake master cylinder - not that there's anything wrong with stock, but it just isn't "stiff" enough for track use (doesn't provide enough pressure?), there is too much movement in the pedal to permit accurate H+T.
My experience against M3s (E30s) at the track is that they have too much handling for a WRX (E36s are a little too quick for me). With your extra power, you should be able to hold your own once the handling is sorted. If you look at the specs though, an STi with a sorted suspension and maybe a revised exhaust, should be able to run with E46s.
For street and track rubber run Azenis. They are fairly inexpensive but grip very well (and can wear quickly). 40lbs hot is a reasonable benchmark for tyres at the track. Start there and adjust accordingly.
Body roll is nasty on WRXs and Stis. I'm sure that you'll work out something with sway bars/springs whatever.
Get used to the understeer. You'll be able to dial some of it out. Stiffen up the rear end and run a lot of negative camber at the front and it will help. I run DMS50s and still have boatloads of understeer in long sweepers. If you think you're getting a lot of understeer at Sears, try turn 2 at Willow! I kill people in turn 1 but when we get to turn 2, they either form a queue behind me or overtake on the [B]outside[/B]. So frustrating!
I think that you might need a new brake master cylinder - not that there's anything wrong with stock, but it just isn't "stiff" enough for track use (doesn't provide enough pressure?), there is too much movement in the pedal to permit accurate H+T.
My experience against M3s (E30s) at the track is that they have too much handling for a WRX (E36s are a little too quick for me). With your extra power, you should be able to hold your own once the handling is sorted. If you look at the specs though, an STi with a sorted suspension and maybe a revised exhaust, should be able to run with E46s.
| teamipr | 10-27-2003 04:53 PM |
Thanks for the input guys!
I'm more used to the setting of lower pressure = better grip. But I guess these tires are not like that. I didn't have a pump with me so I'll try the higher pressure next time.
With my M3, which I don't have anymore, I felt more confident, I can drive it faster. I know the STi is more capable but I think I need to get use to or learn its handling characteristics. It has the power, now I just need to inprove its handling. I'll also switch over to the Azenis after I wear these 070s out. I think new suspension will do the job but I don't want to invest that much $$ into it.
Anyhow, I still had a lot of fun and should have more fun next month.
I'm more used to the setting of lower pressure = better grip. But I guess these tires are not like that. I didn't have a pump with me so I'll try the higher pressure next time.
With my M3, which I don't have anymore, I felt more confident, I can drive it faster. I know the STi is more capable but I think I need to get use to or learn its handling characteristics. It has the power, now I just need to inprove its handling. I'll also switch over to the Azenis after I wear these 070s out. I think new suspension will do the job but I don't want to invest that much $$ into it.
Anyhow, I still had a lot of fun and should have more fun next month.
| Chaste Automotive | 10-27-2003 04:54 PM |
Okay first of all this was your first track day correct? Well the first time in a new car you will have a lotof different sensations and you will not be able to be as bold as you were with your old car. I think that someone posted earlier that what feels fastest is not always the best route. For starters your tire pressures were to low, you will quickly overheat your tires that way (you said you were sliding around) so stick to some higher pressures and experiment. Do not buy anything new for your car since you are not comfortable driving the car the way it is, a big mistake that I see a lot of people make is they have a bad day at the track or autoX course and they go out and buy a bunch of stuff to try and get the correct feeling. Driving AWD is very very different then driving an E36 or an SW20 ( a mid-engined RWD car) yet you have chosen the right car to do it in. Body roll is not a really really bad thing unless you are lifting wheels (wasn't there I have no way to know) cars set way to stiff will understeer just as bad or worse. Are you drining with the Diff set in Auto or are you setting it manually? IF in manual set it all the way back and do a few laps then change the setting and do a few laps until you can find the most comfortable balance. What Line are you taking (the lines you took in your SW or E36 will be different then the fastest AWD line) do you early or late APEX? These are all important questions. I will await your response perhaps we can all help you.
| teamipr | 10-27-2003 05:41 PM |
Chase,
Yeah, this was my first time out in the STi. I'm actually going to keep it as it is for now. I'm planning to run again next month. I'll try using higher pressure next time, I think just to keep it at the factory setting, 36/30 I think.
I don't know if I'm lifting the inside wheels. But I know it has more roll than the stock E36 M3. My DCCD was in auto in the first session. I set it to full rear after that because it felt better. I felt I was doing more throttle steering. BUt I could still feel the front diff kicking in midway through the exit of the corner.
I'm doing mid to late apexes at SP. Is there another line I should take? I felt the car pushed a lot through T6, long downhill banked left corner leading into the back straight. I somtimes get a train going there but then I pull on them on the short straight. I can get a nice run down T8 but the s-turns really brought out the body roll. And the tires were barking all the way through. I hope by increasing the pressure will help.
Yeah, this was my first time out in the STi. I'm actually going to keep it as it is for now. I'm planning to run again next month. I'll try using higher pressure next time, I think just to keep it at the factory setting, 36/30 I think.
I don't know if I'm lifting the inside wheels. But I know it has more roll than the stock E36 M3. My DCCD was in auto in the first session. I set it to full rear after that because it felt better. I felt I was doing more throttle steering. BUt I could still feel the front diff kicking in midway through the exit of the corner.
I'm doing mid to late apexes at SP. Is there another line I should take? I felt the car pushed a lot through T6, long downhill banked left corner leading into the back straight. I somtimes get a train going there but then I pull on them on the short straight. I can get a nice run down T8 but the s-turns really brought out the body roll. And the tires were barking all the way through. I hope by increasing the pressure will help.
| afpdl | 10-27-2003 05:45 PM |
[QUOTE][i]Originally posted by teamipr [/i]
[B]Chase,
. BUt I could still feel the front diff kicking in midway through the exit of the corner.
hope by increasing the pressure will help. B][/QUOTE][
And whats wrong with that? Your supposed to its what allows you to get on the gas way sooner and will pull out out of the understeer. If its not kicking in then its not doing anything better then a open front diff would./
Oh and I would run 38-40 up front and 32-34 in the rear for hot pressures.
[B]Chase,
. BUt I could still feel the front diff kicking in midway through the exit of the corner.
hope by increasing the pressure will help. B][/QUOTE][
And whats wrong with that? Your supposed to its what allows you to get on the gas way sooner and will pull out out of the understeer. If its not kicking in then its not doing anything better then a open front diff would./
Oh and I would run 38-40 up front and 32-34 in the rear for hot pressures.
| fastwrx | 11-01-2003 10:32 PM |
I tracked my 02 WRX several times. I tracked my STi for the first time back in August. I felt the difference was TREMENDOUS. I ran with Falken Azeni Sports.
I found the STi to have far less body roll than the WRX. Power, of course, is night and day. I felt the car was also far more "tossable" and actually liked the way I could tuck in the nose by lifting slightly and then powering out of turns.
I let my instructor, who drives a race-prepped 3-series BMW, drive it a few laps, and he RAVED about my STi.
Next HPDE event is in 2 weeks! Can't wait!
Mike
PS... just put a deposit down for a 2005 Lotus Elise!!!! The wait begins.
I found the STi to have far less body roll than the WRX. Power, of course, is night and day. I felt the car was also far more "tossable" and actually liked the way I could tuck in the nose by lifting slightly and then powering out of turns.
I let my instructor, who drives a race-prepped 3-series BMW, drive it a few laps, and he RAVED about my STi.
Next HPDE event is in 2 weeks! Can't wait!
Mike
PS... just put a deposit down for a 2005 Lotus Elise!!!! The wait begins.
| kfoote | 11-02-2003 10:26 AM |
I ran my STi ad a DE at NHIS a couple of weeks ago, and having driven both E36 M3's and the STi on the track, here are my impressions:
My STi mods from stock: Synthetic oil, 94 octane gas, tire pressures. About as bone stock as you can get.
Tires: Good for street tires, but they are still street tires. If you're going to do more than one or two days in it, get a set of DOT track tires. They felt similar to my experience in a Miata on Hankook full depth DOT track tires in the dry, squishy and squirmy, but not bad. My pressures were 34 cold. Yes, they are loud, and the sharp edges of the tread blocks of the tires are not sharp any more.
Power: The right pedal does something. In the instructor group, pulled 10 car lengths on a Mustang on track tires between 3 (35 MPH tight right) and 5 (top of a hill, <0.2 mi from 3, t4 isn't much of a corner)
Handling: Lots of potential. I did not feel that there was excessive body roll, but then again, the Miata has a ton of it. Body roll in itself is not necessarily a bad thing. Yes, it had power on understeer as all properly setup FWD and AWD cars do. Having learned initialy on FWD cars, switched to RWD, and dabbled in AWD, they all take completely differrent driving styles and require different sets of reactions to get the most out of the car. The car is much more difficult to drive than either the Miata or the E36 M3, and the last 20% of the potential of the car is very difficult to get, but it has the potential to be MUCH faster than the E36 M3.
Brakes: Good, but got fade after 5 laps. I was on the stock pads, and agin, running the car more than once or twice a year, I'd reccommend switching to a racing brake pad. I had no problem heel-toeing until the brakes started to fade, and though it was a bit more difficult, it was still tolerable.
Transmission: Lots of shifting. At NHIS North Oval/South Chicaine, made 10 shifts/lap in the STi compared to 6/lap in the Miata and 5/lap in the standard WRX.
DCCD: Auto mode is bad. At the limit, when the computer decides that the diff should change settings, power is temporarily cut to the wheels. I noticed this on the street, and only ran with the diff in manual mode. I did try a couple of different settings, and the impression I got is that it makes enough of a difference where different tracks would require different settings for ideal performance. On the CA tracks, at Sears you probably want the diff biased more towards open than you would at Laguna.
Impressions on the initial post: The E36 M3 is very close in weight to the STi, but the M3 is a lot easier to get to the limit of than the STi. If you're tring to drive the STi like you drove the M3, you won't be able to get the most out of the car. The single biggest thing that will help the most is that though it's counterintuitive, unwinding the steering wheel more and sooner in the STi (and in the standard WRX as well) helps the front tires hook up better coming out of the corner and allows higher corner exit speed.
Speed: My best STi time, in the 2nd of 3 sessions I ran it (no one timed me in the 3rd) was a 1:25.4. My best Miata time that weekend (SCCA SSB prepped 1999 Miata) 1:30.4. Best WRX time of the weekend (track tires, suspension, electronics): 1:26.5
My STi mods from stock: Synthetic oil, 94 octane gas, tire pressures. About as bone stock as you can get.
Tires: Good for street tires, but they are still street tires. If you're going to do more than one or two days in it, get a set of DOT track tires. They felt similar to my experience in a Miata on Hankook full depth DOT track tires in the dry, squishy and squirmy, but not bad. My pressures were 34 cold. Yes, they are loud, and the sharp edges of the tread blocks of the tires are not sharp any more.
Power: The right pedal does something. In the instructor group, pulled 10 car lengths on a Mustang on track tires between 3 (35 MPH tight right) and 5 (top of a hill, <0.2 mi from 3, t4 isn't much of a corner)
Handling: Lots of potential. I did not feel that there was excessive body roll, but then again, the Miata has a ton of it. Body roll in itself is not necessarily a bad thing. Yes, it had power on understeer as all properly setup FWD and AWD cars do. Having learned initialy on FWD cars, switched to RWD, and dabbled in AWD, they all take completely differrent driving styles and require different sets of reactions to get the most out of the car. The car is much more difficult to drive than either the Miata or the E36 M3, and the last 20% of the potential of the car is very difficult to get, but it has the potential to be MUCH faster than the E36 M3.
Brakes: Good, but got fade after 5 laps. I was on the stock pads, and agin, running the car more than once or twice a year, I'd reccommend switching to a racing brake pad. I had no problem heel-toeing until the brakes started to fade, and though it was a bit more difficult, it was still tolerable.
Transmission: Lots of shifting. At NHIS North Oval/South Chicaine, made 10 shifts/lap in the STi compared to 6/lap in the Miata and 5/lap in the standard WRX.
DCCD: Auto mode is bad. At the limit, when the computer decides that the diff should change settings, power is temporarily cut to the wheels. I noticed this on the street, and only ran with the diff in manual mode. I did try a couple of different settings, and the impression I got is that it makes enough of a difference where different tracks would require different settings for ideal performance. On the CA tracks, at Sears you probably want the diff biased more towards open than you would at Laguna.
Impressions on the initial post: The E36 M3 is very close in weight to the STi, but the M3 is a lot easier to get to the limit of than the STi. If you're tring to drive the STi like you drove the M3, you won't be able to get the most out of the car. The single biggest thing that will help the most is that though it's counterintuitive, unwinding the steering wheel more and sooner in the STi (and in the standard WRX as well) helps the front tires hook up better coming out of the corner and allows higher corner exit speed.
Speed: My best STi time, in the 2nd of 3 sessions I ran it (no one timed me in the 3rd) was a 1:25.4. My best Miata time that weekend (SCCA SSB prepped 1999 Miata) 1:30.4. Best WRX time of the weekend (track tires, suspension, electronics): 1:26.5
| sdecker | 11-03-2003 07:52 AM |
Teamipr:
Hang in there with it. My 02 WRX, which lacks the 6 speed and DCCD but is similar to your STI in terms of power and brakes, can spank E36 M3's and keep up with E46 M3's. I have been known to pass E46 M3's, too...
I've got about 16 total track days under my belt, so I'm not the best driver by a long shot...but the more I drive the car, the better I can drive towards it's limits.
Enjoy it!
Scott
Hang in there with it. My 02 WRX, which lacks the 6 speed and DCCD but is similar to your STI in terms of power and brakes, can spank E36 M3's and keep up with E46 M3's. I have been known to pass E46 M3's, too...
I've got about 16 total track days under my belt, so I'm not the best driver by a long shot...but the more I drive the car, the better I can drive towards it's limits.
Enjoy it!
Scott
| johnfelstead | 11-03-2003 08:38 AM |
First job, get your geometries checked! The car is very sensitive to toe changes.
Run 40psi front, 39psi rear hot tyre presures.
Run the DCCD-A in manual and set it for an open diff in the dry, 25% locked in the wet. If there is a lot of standing water up the diff lock ratio to 75%.
Avoid using the kerbs as the USDM STi has suretrack diffs, these only work if both wheels are on the ground, if you lift a wheel they behave like an open diff so give you strange handling charicteristics as they transition from open to locked when they contact the road. They are a road diff, not a track diff, so bear this in mind.
Try trail braking, the car responds well to that and you can carry more speed into the apex.
Run 40psi front, 39psi rear hot tyre presures.
Run the DCCD-A in manual and set it for an open diff in the dry, 25% locked in the wet. If there is a lot of standing water up the diff lock ratio to 75%.
Avoid using the kerbs as the USDM STi has suretrack diffs, these only work if both wheels are on the ground, if you lift a wheel they behave like an open diff so give you strange handling charicteristics as they transition from open to locked when they contact the road. They are a road diff, not a track diff, so bear this in mind.
Try trail braking, the car responds well to that and you can carry more speed into the apex.
| ToddStratton | 11-03-2003 11:19 AM |
Re: STi Track Experience/Review and Questions
�
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[QUOTE][i]Originally posted by teamipr [/i]
[B]
Handling: Major complaint is there's A LOT of body roll. It feels like the car is just about to go 2 wheels off through the apex.
[/QUOTE]
I haven't seen a stock STi lift a wheel at any autocross or track day. Once it rolls out, it stays planted and is fairly predicatable.
[QUOTE]
Tires: I think the Petenza 070s are crappy track tires. And I think they contribute to the handling faults. They were barking like hell in every corner. I had the pressure set at 31 front and 30 rear cold. They felt like they just wanted to slide.
[/QUOTE]
Pressures have already been addressed, but as far as street tires go, they are good for track work I think. Not as good for autocross IMHO. But yesterday at a track session there wasn't another stock car on street tires that was close to me or the other STi there. In fact, we were faster than most folks in r-compound tires.
Yes, they make a lot of noise, but they are predictable and progressive when they break away.
[QUOTE]
Brakes: GREAT! But the peddel position is not heel-toe friendly.
[/QUOTE]
Yep, the brakes are good.
[QUOTE]
The toothpick thin sway bars need to be changed to thicker ones.
[/QUOTE]
They are 20mm front and rear. I'd think stiffer springs (especially up front) would be a better choice.
[QUOTE]
I know I can drive it faster even in its current stock form. My friend timed me at a fastest time of 2:09 but I did a 2:08 with my M3 before. I'll be going back again in Nov, I hope I can do better then.
Will [/B][/QUOTE]
Within 1 second of your other car on the first day? Change your pressures, get an alignment and toss the car around--finesse is good sometimes, but the STi in stock form seems to like being tossed. That should be good for a couple of seconds. Enjoy!
TRS
[B]
Handling: Major complaint is there's A LOT of body roll. It feels like the car is just about to go 2 wheels off through the apex.
[/QUOTE]
I haven't seen a stock STi lift a wheel at any autocross or track day. Once it rolls out, it stays planted and is fairly predicatable.
[QUOTE]
Tires: I think the Petenza 070s are crappy track tires. And I think they contribute to the handling faults. They were barking like hell in every corner. I had the pressure set at 31 front and 30 rear cold. They felt like they just wanted to slide.
[/QUOTE]
Pressures have already been addressed, but as far as street tires go, they are good for track work I think. Not as good for autocross IMHO. But yesterday at a track session there wasn't another stock car on street tires that was close to me or the other STi there. In fact, we were faster than most folks in r-compound tires.
Yes, they make a lot of noise, but they are predictable and progressive when they break away.
[QUOTE]
Brakes: GREAT! But the peddel position is not heel-toe friendly.
[/QUOTE]
Yep, the brakes are good.
[QUOTE]
The toothpick thin sway bars need to be changed to thicker ones.
[/QUOTE]
They are 20mm front and rear. I'd think stiffer springs (especially up front) would be a better choice.
[QUOTE]
I know I can drive it faster even in its current stock form. My friend timed me at a fastest time of 2:09 but I did a 2:08 with my M3 before. I'll be going back again in Nov, I hope I can do better then.
Will [/B][/QUOTE]
Within 1 second of your other car on the first day? Change your pressures, get an alignment and toss the car around--finesse is good sometimes, but the STi in stock form seems to like being tossed. That should be good for a couple of seconds. Enjoy!
TRS
| ToddStratton | 11-03-2003 11:30 AM |
[QUOTE][i]Originally posted by johnfelstead [/i]
[B]First job, get your geometries checked! The car is very sensitive to toe changes.
Run 40psi front, 39psi rear hot tyre presures.
Run the DCCD-A in manual and set it for an open diff in the dry, 25% locked in the wet. If there is a lot of standing water up the diff lock ratio to 75%.
Avoid using the kerbs as the USDM STi has suretrack diffs, these only work if both wheels are on the ground, if you lift a wheel they behave like an open diff so give you strange handling charicteristics as they transition from open to locked when they contact the road. They are a road diff, not a track diff, so bear this in mind.
Try trail braking, the car responds well to that and you can carry more speed into the apex. [/B][/QUOTE]
My impression of the DCCD in auto is pretty good in the rain. As I get better I'm sure I'll play with manual locking ratios in the future for wet days. For now I stick with auto in rain and auto or manual full open in the dry, depending on how I feel.
Good point about the curbs. We get a slight break since our rear diff is a mechanical clutch type, but the front is a suretrac.
TRS
[B]First job, get your geometries checked! The car is very sensitive to toe changes.
Run 40psi front, 39psi rear hot tyre presures.
Run the DCCD-A in manual and set it for an open diff in the dry, 25% locked in the wet. If there is a lot of standing water up the diff lock ratio to 75%.
Avoid using the kerbs as the USDM STi has suretrack diffs, these only work if both wheels are on the ground, if you lift a wheel they behave like an open diff so give you strange handling charicteristics as they transition from open to locked when they contact the road. They are a road diff, not a track diff, so bear this in mind.
Try trail braking, the car responds well to that and you can carry more speed into the apex. [/B][/QUOTE]
My impression of the DCCD in auto is pretty good in the rain. As I get better I'm sure I'll play with manual locking ratios in the future for wet days. For now I stick with auto in rain and auto or manual full open in the dry, depending on how I feel.
Good point about the curbs. We get a slight break since our rear diff is a mechanical clutch type, but the front is a suretrac.
TRS
| kfoote | 11-03-2003 01:19 PM |
Re: Re: STi Track Experience/Review and Questions
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[QUOTE][i]Originally posted by ToddStratton [/i]
[B]
I'd think stiffer springs (especially up front) would be a better choice.
[/B][/QUOTE]
I totally agree with this, and the more I drive the car, the more stiffer springs, especially in the front, makes sense.
[B]
I'd think stiffer springs (especially up front) would be a better choice.
[/B][/QUOTE]
I totally agree with this, and the more I drive the car, the more stiffer springs, especially in the front, makes sense.
| FSelekler | 11-03-2003 01:42 PM |
In our tests we found that the 070s while they have over 70% of their thread respond very well with 36.5f and 38r pressures.
Thread below 70% the pressures need to be increased to 39f/39r for short and technical tracks or autoxes, 38f/39r for fast tracks with few hairpins or sweepers.
As it is mentioned before, the body roll is an issue with the STi, but that also gives its very forgiving nature. Trail-braking is very predictable. However, positive camber changes are also very noticeable. Our first recommended upgrade will be the A/R bars front and back.
Thread below 70% the pressures need to be increased to 39f/39r for short and technical tracks or autoxes, 38f/39r for fast tracks with few hairpins or sweepers.
As it is mentioned before, the body roll is an issue with the STi, but that also gives its very forgiving nature. Trail-braking is very predictable. However, positive camber changes are also very noticeable. Our first recommended upgrade will be the A/R bars front and back.
| brogliei | 11-03-2003 06:37 PM |
Well, I drive my WRX at a local track quite a bit per year and I got to drive my friends STi this past event. I have to say there is no comparison between the two cars.
My WRX is stock right now, but I have had it setup with DMS40s, 17s w/R-comp tires, Turboxs Stg4 and Carbotech P+ pads. With my modified setup I could almost keep up with the ZO6s (on street tires) driven by instructors (they are just to fast on slicks), I could turn 1:34-5 on average with that setup. Currently my WRX is stock with 225/50/16 MXs (40f and 38r) and I can turn a 1:38, but average 1:39 or so. Please note that this track is a very tight and technical course, the Z06s only get to 104 or so a the end of the front straight.
First thing you notice with the STi is the power and torque is remarkable combined with the 6 speed. I hit the rev limiter a few times trying to drive it similar to my WRX, the short gearing caught me off guard a few times until I got in the grove. This thing just powers through corners that my WRX just plain lags on. I hit 101 on the front straight and my WRX only hits 85. The WRX just plain sucks when you live on the course either between 6-7K rpm or out of a hairpin in sencond at 3K rpm. Power delivery out of the two slow hairpins is so nice that that along takes a couple second off the lap times.
Second the handling was very balanced, but coming off of my stock WRX it felt very twitchy at the start. Once you get used to the small sudlties of the STi it really moves in and out of corners. I actually like it a ton better than my WRX when it had M2 DMS40s. I still think the STi could use some 245 wide rubber though.
Third the brakes are phenominal. They need much wider tires to give them some real work. They don't even break a sweat on this course, the speeds are just not high enough and you get plenty of time between hard breaking corners.
As for times, the STi is an easy 1:34 and quite possible has a 1:33 in it on a good lap (which my buddy did do once). This is on the 070s of course.
As for trying to drive the car like a RWD, it just won't work. Even someone who is acustomed to driving a FWD would have a hard time getting used to the characteristics of a really good AWD system.
My experience with this car can be described in one word - AMAZING! I don't consider myself a great driver by any means, but I can get a WRX around the track in decent time. The STi is like night and day compaired to the WRX and worlds different from any RWD or FWD car.
Keep up the practice with AWD they can be really fast track cars if driven like an AWD is supposed to be.
good luck
peace
Ian
My WRX is stock right now, but I have had it setup with DMS40s, 17s w/R-comp tires, Turboxs Stg4 and Carbotech P+ pads. With my modified setup I could almost keep up with the ZO6s (on street tires) driven by instructors (they are just to fast on slicks), I could turn 1:34-5 on average with that setup. Currently my WRX is stock with 225/50/16 MXs (40f and 38r) and I can turn a 1:38, but average 1:39 or so. Please note that this track is a very tight and technical course, the Z06s only get to 104 or so a the end of the front straight.
First thing you notice with the STi is the power and torque is remarkable combined with the 6 speed. I hit the rev limiter a few times trying to drive it similar to my WRX, the short gearing caught me off guard a few times until I got in the grove. This thing just powers through corners that my WRX just plain lags on. I hit 101 on the front straight and my WRX only hits 85. The WRX just plain sucks when you live on the course either between 6-7K rpm or out of a hairpin in sencond at 3K rpm. Power delivery out of the two slow hairpins is so nice that that along takes a couple second off the lap times.
Second the handling was very balanced, but coming off of my stock WRX it felt very twitchy at the start. Once you get used to the small sudlties of the STi it really moves in and out of corners. I actually like it a ton better than my WRX when it had M2 DMS40s. I still think the STi could use some 245 wide rubber though.
Third the brakes are phenominal. They need much wider tires to give them some real work. They don't even break a sweat on this course, the speeds are just not high enough and you get plenty of time between hard breaking corners.
As for times, the STi is an easy 1:34 and quite possible has a 1:33 in it on a good lap (which my buddy did do once). This is on the 070s of course.
As for trying to drive the car like a RWD, it just won't work. Even someone who is acustomed to driving a FWD would have a hard time getting used to the characteristics of a really good AWD system.
My experience with this car can be described in one word - AMAZING! I don't consider myself a great driver by any means, but I can get a WRX around the track in decent time. The STi is like night and day compaired to the WRX and worlds different from any RWD or FWD car.
Keep up the practice with AWD they can be really fast track cars if driven like an AWD is supposed to be.
good luck
peace
Ian
| Impreza01 | 11-04-2003 06:34 PM |
Just wondering, maybe part of the reason you're not use to the body roll is because the STi is a long travel suspension (struts all around)? As opposed to teh E36 M3 which had a short travel suspension in the back (struts front and multilink or whast it a double wishbone in teh back). Supposedly the STi has a long travel suspension because of the WRC car which is better at Gravel stages than Tarmac Stages.
As for teh front LSD, it's because it's a 1 way LSD, so when on power, the LSD will lock and feel great, but off power the LSD does nothing. This can be changed with a 2-way LSD, but that type of LSD is said to be for those doing pro racing (dunno why).
EDIT: Nevermind what I said, the MR2 has struts all around like the STi.
As for teh front LSD, it's because it's a 1 way LSD, so when on power, the LSD will lock and feel great, but off power the LSD does nothing. This can be changed with a 2-way LSD, but that type of LSD is said to be for those doing pro racing (dunno why).
EDIT: Nevermind what I said, the MR2 has struts all around like the STi.
| Sergeant_V | 11-05-2003 07:40 AM |
[QUOTE]I didn't feel as confident in the STi as I did in the M3. And I'm not use to the pulling of the car at the exit of corners. The car pushes at the exit as I get on the gas and then the front diff binds and pulls the car. A bid weird feeling...I'm not used to that.[/QUOTE] Since all of your track experience is with RWD cars you may be having a hard time resisting the instinct to countersteer as the car starts to roll and you anticipate oversteer. Check out this article about STi handling on the [URL=http://www.apexjapan.com/editorial/randomness.html]Apex Japan[/URL] website.
| brogliei | 11-05-2003 09:50 AM |
Damn Abel you have one too. You lucky bastard. :)
teamipr - a few more track days in the STi and you will get the gist of how the car likes to be handled.
peace
Ian
teamipr - a few more track days in the STi and you will get the gist of how the car likes to be handled.
peace
Ian
| Mikko | 11-06-2003 06:47 AM |
I thought the Impreza WRX STi comes with an adjustable torque setting - either 50/50 or 30/70. That kind of setting should give it a very RWD feel - and if ever start to powerslide, needs to be countersteered.
| kfoote | 11-06-2003 09:48 AM |
[QUOTE][i]Originally posted by Mikko [/i]
[B]I thought the Impreza WRX STi comes with an adjustable torque setting - either 50/50 or 30/70. That kind of setting should give it a very RWD feel - and if ever start to powerslide, needs to be countersteered. [/B][/QUOTE]
You can adjust the DCCD to change the percentage lockup of the center LSD, but even at fully open, though the car can get tail happy, it still has to be driven as an AWD car. In a lot of cases, the reaction set that has been developed having driven a RWD car on the track doesn't work, and the combination of steering and throttle input needed can be different in an RWD and a FWD car in the same situation.
[B]I thought the Impreza WRX STi comes with an adjustable torque setting - either 50/50 or 30/70. That kind of setting should give it a very RWD feel - and if ever start to powerslide, needs to be countersteered. [/B][/QUOTE]
You can adjust the DCCD to change the percentage lockup of the center LSD, but even at fully open, though the car can get tail happy, it still has to be driven as an AWD car. In a lot of cases, the reaction set that has been developed having driven a RWD car on the track doesn't work, and the combination of steering and throttle input needed can be different in an RWD and a FWD car in the same situation.
| Sergeant_V | 11-06-2003 03:07 PM |
"You don't want to countersteer, no matter how much that has been hardwired in your brain for whatever reason. You just carefully modulate the throttle and keep the front pointed in the direction that you want to go. That's because the semi-trick centre differential is going to try and save your a$$ for you, and it's pointless arguing with it."
from an article about the JDM STi ver. 8 by Paul Hansen
from an article about the JDM STi ver. 8 by Paul Hansen
| Mikko | 11-06-2003 03:16 PM |
If you are in a powerslide, the differentials can't do much to save you. It is possible that a computer could manipulate the brakes (like ESP) and engine output in order to straighten the car out, but that would be boring.
I am aware of the active limited slip settings - but what about the actual power distribution settings? 70% rear power gives very rear wheel drive behaviour.
I am aware of the active limited slip settings - but what about the actual power distribution settings? 70% rear power gives very rear wheel drive behaviour.
| Sergeant_V | 11-06-2003 04:40 PM |
My understanding of the DCCD is based primarily on the excellent DCCD FAQ you can find [URL=http://wallace.as.arizona.edu/~cgroppi/DCCD_FAQ/DCCD_FAQ.html]here[/URL] . In an oversteer condition the rear axle is unlikely to see 70% of the available torque. How much is available at each axle will depend on how the DCCD is set (from open to full lock) and how much traction is available. As the torque is shifted from the wheels that slip to those that grip you'll definitely want the fronts pointed in the direction you want to go, not countersteering.
| Mikko | 11-07-2003 02:37 AM |
I read select parts of it and it doesn't make any sense to me.
A mechanical differential will ALWAYS try to attempt to send the power to the path that offers the least resistance.
And the limited-slip mechanics can ONLY try to prevent that by bringing it back to a maximum of the original, fixed ratio (trying to force them, to different degrees, to rotate at the same speed, if the original ratio was 50 front and 50 rear - or 50 left, 50 right, etc).
As far as I am aware, only Porsche 959, which had a huge, heavy, durable, triple or more, clutch pack as center active differential, could vary the actual torque split between front and rear while the car was moving. Peugeot 205 T16 Group B car could vary the split from within the car when standing still.
Lancer EVO's super AYC though, not sure exactly how that works.. :confused:
A mechanical differential will ALWAYS try to attempt to send the power to the path that offers the least resistance.
And the limited-slip mechanics can ONLY try to prevent that by bringing it back to a maximum of the original, fixed ratio (trying to force them, to different degrees, to rotate at the same speed, if the original ratio was 50 front and 50 rear - or 50 left, 50 right, etc).
As far as I am aware, only Porsche 959, which had a huge, heavy, durable, triple or more, clutch pack as center active differential, could vary the actual torque split between front and rear while the car was moving. Peugeot 205 T16 Group B car could vary the split from within the car when standing still.
Lancer EVO's super AYC though, not sure exactly how that works.. :confused:
| MNbiker | 11-07-2003 09:06 AM |
[QUOTE][i]Originally posted by Mikko [/i]
[B]I read select parts of it and it doesn't make any sense to me.
[/B][/QUOTE]
Try this link for an excellent primer:
[URL=http://wallace.as.arizona.edu/~cgroppi/DCCD_FAQ/DCCD_FAQ.html]DCCD FAQ - PART 1[/URL]
-Steve
[B]I read select parts of it and it doesn't make any sense to me.
[/B][/QUOTE]
Try this link for an excellent primer:
[URL=http://wallace.as.arizona.edu/~cgroppi/DCCD_FAQ/DCCD_FAQ.html]DCCD FAQ - PART 1[/URL]
-Steve
| afpdl | 11-07-2003 09:19 AM |
[QUOTE][i]Originally posted by MNbiker [/i]
[B]Try this link for an excellent primer:
[URL=http://wallace.as.arizona.edu/~cgroppi/DCCD_FAQ/DCCD_FAQ.html]DCCD FAQ - PART 1[/URL]
-Steve [/B][/QUOTE]
HA Im on the contributors list on that webpage, misspelled but still on there. :lol: Only thing is I have not idea what I contributed:huh:
[B]Try this link for an excellent primer:
[URL=http://wallace.as.arizona.edu/~cgroppi/DCCD_FAQ/DCCD_FAQ.html]DCCD FAQ - PART 1[/URL]
-Steve [/B][/QUOTE]
HA Im on the contributors list on that webpage, misspelled but still on there. :lol: Only thing is I have not idea what I contributed:huh:
| sethtasy | 11-07-2003 04:00 PM |
[QUOTE][i]Originally posted by afpdl [/i]
[B]HA Im on the contributors list on that webpage, misspelled but still on there. :lol: Only thing is I have not idea what I contributed:huh: [/B][/QUOTE]
:lol: Well as the author, I guess I'm the only one can answer that one. Back when I was first trying to understand the DCCD, you had a post in "Leonardo's big DCCD thread" that linked to some information that was very helpful. Sorry for the misspell, I'll ask cgroppi to change it.
LSDs are a pain to really understand. Based on other discussions with nasioc members, that document still needs a few small clarifications and adjustments. If anyone wants to discuss the article, i.e. tell me how and why I am wrong, or get some clarifications, or just offer suggestions, I think it would be best to use a thread I started in the transmission forum. You'd have to search to find it.
Seth
[B]HA Im on the contributors list on that webpage, misspelled but still on there. :lol: Only thing is I have not idea what I contributed:huh: [/B][/QUOTE]
:lol: Well as the author, I guess I'm the only one can answer that one. Back when I was first trying to understand the DCCD, you had a post in "Leonardo's big DCCD thread" that linked to some information that was very helpful. Sorry for the misspell, I'll ask cgroppi to change it.
LSDs are a pain to really understand. Based on other discussions with nasioc members, that document still needs a few small clarifications and adjustments. If anyone wants to discuss the article, i.e. tell me how and why I am wrong, or get some clarifications, or just offer suggestions, I think it would be best to use a thread I started in the transmission forum. You'd have to search to find it.
Seth
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