AutoX'ers THREAD

[7Mboost]

The purpose of this thread is to share suspension and tuning setups for autocross/ short course/ road course events. Keep the thread uncluttered, post about suspension, setups, experiences, and questions dealing with them.

I just did my first short course AutoX at Gainesville Road Course in my home town and I am hooked. I went out with no alignment, 235 & 255 Sumitomo tires, Bilstein struts/Eibach springs, ST sways, and only got time to install my rear poly bushings and had a blast, some of the most fun I've experienced with my car so far.

My analysis of my first track event (with turns ):

The Sumitomo's suck, there is one mid 2nd gear 180 degree turn where my car would plow straight will these tires, idk if it more due to the tires or lack of poly bushings, and having poly's in the back with the ST sway set to full stiff.

What I am thinking about changing:

New Kuhmo XS's, 245 & 275 (MKIV wheels), an alignment -1.5" Front -0.8R", EBC or Hawk pads (I also have 13" Mustang Cobra brakes in the front- Dowards), and install the rest of the poly bushings.

Questions (some random):

What brakes are you guys running?
Alignment specs (and is it set off courses you run)?
Suspension, is streetable and trackable?
Tires?
Classes in SCCA?
A lot more questions to come just have to remember them.

I'm looking to improve my knowledge in this feild and represent the MKIII on the twisties! Corner Carvers, post up.

 

[CyFi6]

Im on stock rims with some el cheapo's. Stock alignment settings, stock bushings and everything, only upgrade is Megan Racing coil overs which i don't like that much. Ive taken it to two auto x events and it only performed decently with my fronts on full stiff and my rears on full soft. (this is what i run it with on the street all the time). Running Toyota pads on OEM rotors. Im NA though, and it seems to stop good enough for my driving abilities. I have never really done very well, but i always have a blast!

The Supra is pretty front heavy and doesn't seem to be the best choice for autocross, but it still does OK if you know what youre doing.

 

[Sawbladz]

I've run one auto-X which took place at Picton airfield up here in Canada. It is extremely fast for an auto-X. I think I got the car into third for a few seconds on the long straight. My car handled very flat and didn't push as much as I had expected. I think the best way for me to fix this would be with tires (too much stagger for racing). I only have stock brakes but I didn't notice them fade. This isn't surprising because the entire course was only a minute long. The only cars which were faster than me were a C4 Corvette, an older Porsche 911 turbo and a heavily modded Fox body.

MODS:

full poly bushings, HSD coilovers set decently stiff, Brembo rotors and porterfield pads, LIPP trailing arms, braided brake lines, 225 Bridgestone Potenza pole positions in front, 275 Goodyear Eagle F1 GSD3's in rear, 280 whp.

MODS wanted: Driver mod, sway bars, bigger front tires (245+), Cobra brakes, working LSD

 

[supraguru05]

mk3 turbo supras can be competitive in ESP on a local level but not so much on a national level
mk3 na supras can be competitive in the stock class which if i remember right is GS.

I have autocrossed for over 5 years in my supra (since i was 16). my initial suspension setup for most of those years was eibacs, konis, st sways. i am now dialing in my bilstein coilover setup with the st sways. as far as brakes metal masters are fine for autocross and are cheap. im running 275 azenis but my car is now for road racing not really autocross so the car is a little stiff for autocross as i have 850lb front springs and 400lb rear springs. for autocross traction arms are important as are rear bushing since wheel hop is really bad off the line. if people have questions feel free to ask

 

[rcsupra]

I do a few local auto-x's a year; my car's suspension is all stock except for ST sways. Its a blast, even though the local courses usually favor lighter, better handling cars like Miatas etc.

I'm planning on doing the Tokico/Eibach combo or something similar, and getting a set of 18's (likely staggered)...I'm interested to see how those mods affect things.

7Mboost, what Sumitomos do you have? I have HTRZII's and they're awesome; leagues and bounds better than the Yoko AVS ES100's I had before. They grip and wear much better. I think the plowing issue you're having could be partially attributed to the staggered MKIV TT wheels and tire sizes...also you might want to try softening up that rear bar and stiffening the front bar (mine are both in the neutral settings)

The guys I auto-x with have more capable cars, so I get the most jokes...

 

[prsrcokr]

My name is Brian and I'm addicted to motorsports....

I've been autoxing for a few years and have done several track events. Here's my current setup:
Bolt on engine stuff (IC, piping, exhaust, injectors, ecu, MBC-14psi), Buddyclub coilovers (18k/10k-1000lb/600lb), front Tanabe swaybar, rear ST bar, strut bars, nylon bushings, 235/255-17 Azenis, Al. flywheel and DS, Southbend kevlar clutch. Pads are Porterfield R4S pads (auto-x) and Raybestos ST-41(F) Porterfeild R-41 (R, track) blank rotors and braided lines, Valvoline brake fluid (old formula, new blue bottle is lower dry/wet BP)
I'd guess I'm around 300-320 at the crank (engine is original, 200k)

Alignment was: front -0.8 deg. camber, rear -2.0 deg. camber, stock castor, minimal toe, current alignment is: -1.0 deg. camber, rear -1.5 deg. camber, stock castor, minimal toe.

I've just switched to the Buddyclub setup (used) and was running Tokico/Eibach. I thought that was a good setup since is was smooth for normal driving and fairly stiff for auto-x/track. I also liked the spring ratio (F/R) but felt like it allowed too much dive once I learned to really maximize the traction. My first tires were some old Dunlops that came with the wheels I was running (Volks, currently FS ~ ) then on to Bridgestone S-03's, now Azenis and I have some used 235/255 RA-1s waiting for the Azenis to die. My learning path was to get all I felt I could out of the old tires then move to something better, then a little better than that, so on.

I like the brake setup, I don't fade the race pads (even with dust shields in place) but have faded the R4S (street pads) on track. Also learning brake management is helpful in controlling/reduced heatsoak in the brakes (learning to brake hard and not too long, I have to constantly remind myself not to do this) My tires are relatively narrow but very easy to lock up, instructors on 275 V10's have mentioned they can easily lockup tires with the Raybestos pads as well. My reason for bigger brakes will be first weight, second to combat heat.

So far I like the Buddyclub setup, I didn't want rates this high (was aiming for ~850/400 like guru but gave up on trying to build my own coilovers. Tein & HKS upper mounts don't work with 2.5" springs as an FYI. It is surprisingly smooth, not harsh like I thought it would be.

When I had the ST front bar I had alot of oversteer (tail happy) with the heavier front bar (Tanabe) it's pretty nuetral with a slight oversteer bias (easy to throttle steer) which I like. I would like to see if a softer rear bar (ST rear is already set to soft) like a stock bar might allow me to run square tire sizes and still be fairly nuetral (need more front tire to help braking) To the OP, I didn't have big oversteer until I put the bushings in, probably because the susp. had alot of slop and partly because I was learning the car (was done the first few months of auto-xing) For the first 3 years, the only big thing I changed was the front bar and tires, I recently did the clutch/FW/DS/suspension/roll bar and am doing some relearning.

If anyone has questions (I know I'm missing some things) let me know. As our Nasa-x/TT director says, 'first thing to fix is the loose nut behind the wheel' I'm still reminding myself of that constantly.
Brian

I run mainly with NASA (auto-x and HPDE's) in NXD class and prepping for TTD class. I'll be able to run wider RA-1's in TT (255/275) but am not licensed yet. I ran ESP with SCCA, I'd agree the mk3 will not be competitive on the big circuit in that class. Also don't think the N/A would do well in GS, it's been a Mini-dominated class. Locally you'll have fun in either most likely (altough we have several ASP, ESP, HS, GS, etc champs in our area, the guys that run the EVO school if anyone's heard of it.)

I like NASA's format because it's points based, not mod based. So you could have a carbon hood and still be in the entry class for your car whereas SCCA puts you into a heavily modded class for a single upgrade (although their classing also has advantages)
You can also run weight based vs. weight-reduction points based w/ NASA. Right now I'm a tick over 3700 with me in the car, the base weight is 3531 so I can remove down to that weight without penalty.

 

[7Mboost]

I've run one auto-X which took place at Picton airfield up here in Canada. It is extremely fast for an auto-X. I think I got the car into third for a few seconds on the long straight. My car handled very flat and didn't push as much as I had expected. I think the best way for me to fix this would be with tires (too much stagger for racing). I only have stock brakes but I didn't notice them fade. This isn't surprising because the entire course was only a minute long. The only cars which were faster than me were a C4 Corvette, an older Porsche 911 turbo and a heavily modded Fox body.

MODS:

full poly bushings, HSD coilovers set decently stiff, Brembo rotors and porterfield pads, LIPP trailing arms, braided brake lines, 225 Bridgestone Potenza pole positions in front, 275 Goodyear Eagle F1 GSD3's in rear, 280 whp.

MODS wanted: Driver mod, sway bars, bigger front tires (245+), Cobra brakes, working LSD

I assume understeer is aplenty with the tire width offset? haha. 17's/18's? Fenders rolled?

7Mboost, what Sumitomos do you have? I have HTRZII's and they're awesome; leagues and bounds better than the Yoko AVS ES100's I had before. They grip and wear much better. I think the plowing issue you're having could be partially attributed to the staggered MKIV TT wheels and tire sizes...also you might want to try softening up that rear bar and stiffening the front bar (mine are both in the neutral settings)

The guys I auto-x with have more capable cars, so I get the most jokes...

Both bars are set to full stiff (ST's). Its hard to say if it's a sway bar or bushing thing when I found the front rubber control arm bushings done the other day... I would think having more flex in the front and a stiff rear would help the rear end kick out when I need it? The turn that got me was a ~3,000RPM 2nd gear (3.73 gear, R154, 235-45-17F 255-45-17R) 180 degree corner. My 62-1 does not spool that quick and I don't think first gear is really an option when the straight prior to it is at the top of 2nd gear, do you guys ever downshift to 1st?!

My name is Brian and I'm addicted to motorsports....

I've been autoxing for a few years and have done several track events. Here's my current setup:
Bolt on engine stuff (IC, piping, exhaust, injectors, ecu, MBC-14psi), Buddyclub coilovers (18k/10k-1000lb/600lb), front Tanabe swaybar, rear ST bar, strut bars, nylon bushings, 235/255-17 Azenis, Al. flywheel and DS, Southbend kevlar clutch. Pads are Porterfield R4S pads (auto-x) and Raybestos ST-41(F) Porterfeild R-41 (R, track) blank rotors and braided lines, Valvoline brake fluid (old formula, new blue bottle is lower dry/wet BP)
I'd guess I'm around 300-320 at the crank (engine is original, 200k)

Alignment was: front -0.8 deg. camber, rear -2.0 deg. camber, stock castor, minimal toe, current alignment is: -1.0 deg. camber, rear -1.5 deg. camber, stock castor, minimal toe.

I've just switched to the Buddyclub setup (used) and was running Tokico/Eibach. I thought that was a good setup since is was smooth for normal driving and fairly stiff for auto-x/track. I also liked the spring ratio (F/R) but felt like it allowed too much dive once I learned to really maximize the traction. My first tires were some old Dunlops that came with the wheels I was running (Volks, currently FS ~ ) then on to Bridgestone S-03's, now Azenis and I have some used 235/255 RA-1s waiting for the Azenis to die. My learning path was to get all I felt I could out of the old tires then move to something better, then a little better than that, so on.

I like the brake setup, I don't fade the race pads (even with dust shields in place) but have faded the R4S (street pads) on track. Also learning brake management is helpful in controlling/reduced heatsoak in the brakes (learning to brake hard and not too long, I have to constantly remind myself not to do this) My tires are relatively narrow but very easy to lock up, instructors on 275 V10's have mentioned they can easily lockup tires with the Raybestos pads as well. My reason for bigger brakes will be first weight, second to combat heat.

So far I like the Buddyclub setup, I didn't want rates this high (was aiming for ~850/400 like guru but gave up on trying to build my own coilovers. Tein & HKS upper mounts don't work with 2.5" springs as an FYI. It is surprisingly smooth, not harsh like I thought it would be.

When I had the ST front bar I had alot of oversteer (tail happy) with the heavier front bar (Tanabe) it's pretty nuetral with a slight oversteer bias (easy to throttle steer) which I like. I would like to see if a softer rear bar (ST rear is already set to soft) like a stock bar might allow me to run square tire sizes and still be fairly nuetral (need more front tire to help braking) To the OP, I didn't have big oversteer until I put the bushings in, probably because the susp. had alot of slop and partly because I was learning the car (was done the first few months of auto-xing) For the first 3 years, the only big thing I changed was the front bar and tires, I recently did the clutch/FW/DS/suspension/roll bar and am doing some relearning.

If anyone has questions (I know I'm missing some things) let me know. As our Nasa-x/TT director says, 'first thing to fix is the loose nut behind the wheel' I'm still reminding myself of that constantly.
Brian

I run mainly with NASA (auto-x and HPDE's) in NXD class and prepping for TTD class. I'll be able to run wider RA-1's in TT (255/275) but am not licensed yet. I ran ESP with SCCA, I'd agree the mk3 will not be competitive on the big circuit in that class. Also don't think the N/A would do well in GS, it's been a Mini-dominated class. Locally you'll have fun in either most likely (altough we have several ASP, ESP, HS, GS, etc champs in our area, the guys that run the EVO school if anyone's heard of it.)

I like NASA's format because it's points based, not mod based. So you could have a carbon hood and still be in the entry class for your car whereas SCCA puts you into a heavily modded class for a single upgrade (although their classing also has advantages)
You can also run weight based vs. weight-reduction points based w/ NASA. Right now I'm a tick over 3700 with me in the car, the base weight is 3531 so I can remove down to that weight without penalty.

I've been wanting to talk to you. I want to run street tires, what do you prefer? I've heard great things about Kuhmo MX, XS and the new Dunlop Direzza Star Specs (Best bang for buck tires). How are Toyo street tires and can you compare them to the tires above?

Is my Bilstein/Eibach setup too soft? I have nothing else to compare it to and I can say it feel good and fast but I really can't provide input till I put in the bushings and real tires.

 

[SupraOfDoom]

I can see auto-x's from my house I've been meaning to get into it forever but never had the money for a reliable supra to play.

 

[supraguru05]

I've been wanting to talk to you. I want to run street tires, what do you prefer? I've heard great things about Kuhmo MX, XS and the new Dunlop Direzza Star Specs (Best bang for buck tires). How are Toyo street tires and can you compare them to the tires above?

Is my Bilstein/Eibach setup too soft? I have nothing else to compare it to and I can say it feel good and fast but I really can't provide input till I put in the bushings and real tires.

tires for autocross or road racing?

 

[7Mboost]

tires for autocross or road racing?

More of a small, local road course.

 

[supraguru05]

More of a small, local road course.

Brian had success with pole position SO3s or for cheaper use khumho MXs. I ran those and they were dead after about 10 autocross and 4 or 5 track weekends. The tires had tread left but they started to chunk. azenis and the star specs will not be able to take the heat

 

[NCSupraowner]

I'm auto-x'ing as well. The car seems to do ok at auto-x speeds, but above about 60 mph I have a lot of sway or wander in the rear end. I'm all stock suspension wise except for G35 wheels, which add height and sidewall, and that may be my problem.

 

[prsrcokr]

My 62-1 does not spool that quick and I don't think first gear is really an option when the straight prior to it is at the top of 2nd gear, do you guys ever downshift to 1st?!


I've been wanting to talk to you. I want to run street tires, what do you prefer? I've heard great things about Kuhmo MX, XS and the new Dunlop Direzza Star Specs (Best bang for buck tires). How are Toyo street tires and can you compare them to the tires above?

Is my Bilstein/Eibach setup too soft? I have nothing else to compare it to and I can say it feel good and fast but I really can't provide input till I put in the bushings and real tires.

I wouldn't ever shift to 1st, it's very hard on many things (synchros, mounts, etc) as you know 1st is pretty short in these cars and once you get the flow of things, you won't need to any any SCCA/NASA style course. Luckily, you've got an I-6 with decent torque to help out in those lower rev corners.

I'm not on the Toyo's yet but they're considered an R'comp (100 rating) currently on Azenis (200 rating) the Azenis were great when new but I think they're heat cycled out (don't grip that well now) The newer street tires are something I'll look into for a street/cold weather/wet tire. They have a 140 rating and I've seen some unbelievable times run on some of them, faster than my Azenis which I was able to do a lot with when new. I think either the new Kuhmo or new Dunlop will do very well, especially since you'll get feedback of a street tire to help with learning (I've been told many R's don't give much audible feedback and the far side of the slip angle can be steep, meaning once you're beyond the limit it's hard to come back)

I thought the Eibach setup was pretty good, it gave good feedback and transitioned well (with bushings and good swaybars in place) My reason for changing was that I wanted to reduce dive hoping to find some time in reducing transition time. I don't need it for my street tires since I really liked the setup but figured I would once I move to stickier tires and then to wider, stickier tires.

 

[prsrcokr]

Brian had success with pole position SO3s or for cheaper use khumho MXs. I ran those and they were dead after about 10 autocross and 4 or 5 track weekends. The tires had tread left but they started to chunk. azenis and the star specs will not be able to take the heat

I suspect the same guru but will be taking the Azenis to their first full track event next weekend. They're undersized for the weight 9235/255) so may overheat but are pretty hard now so may do ok. The S03's really didn't get greasy as they heated slower, depends on how hard you push them. I'd been told MX's did well for track use but that was from lighter cars (Vettes, etc) and a Cobra friend liked the Azenis but he was on 275's.

 

[supraguru05]

my Khumho MXs were 255s and worked fine at the track. if you feel the azenis getting greasey just give em a one lap break and they should come back no problem.

 

[SupraOfDoom]

Anyone running a GT35R sized turbo in autox? I realize that's kind over kill but it does spool quickly.

 

[7Mboost]

Anyone running a GT35R sized turbo in autox? I realize that's kind over kill but it does spool quickly.

62-1 here, I assume a GT35R BB or DBB will spool a ton quicker and I have no trouble other than running out of RPM rev range in one low RPM 2nd gear corner corner which I might have cured.

Alright guys looks like I'm gonna go with some Kuhmo MX's. I have MKIV TT wheels for my track wheels, what kind of meat should I stuff under them without rubbing? (I have no fender liners)

 

[7Mboost]

Will 275R and 245F on mkiv wheels fit without rubbing?

 

[prsrcokr]

It'll depend on ride height. 275's look like they'll fit on my setup, might have to check yours since the mk4 wheel offset is closer in (mine are 17x10 + 35) not sure of the offset you have. On the front I test fit the rears (255 width) and the outside of the tire was just hitting the fender liner at full turn. I would think you'd be ok with a 245 since those wheels sit further in.

Have an update on the Azenis, last weekend was 90+ and Sunny. This was the first hot track weekend I've done. Have been purposely trying to avoid Summer heat track events due to engine age and stock cooling (OEM replacement CSF radiator, original PS & oil coolers) I was deffinitely one of the slower ones of the group, tires were gettting greasy on the second lap at times and was watching the temp. gauge rise a lot so never could do full laps pushing the tires and engine. The fact the the car made it through an entire weekend of this was impressive though. Temp. gauge was climbing to a couple ticks below red, pitted at one time to make sure it wasn't something else and the temps came right back down so I was letting it climb past normal range and then letting it come back. Same with the tires, they had good grip and the instructor was impressed with the braking/cornering on street tires but they were really getting overheated even though I wasn't pushing hard (235/255 sizes). I think they'd be fine in a wider size in fall weather (50-60 deg. F) but deffinitely not in the more narrow size I was running in 90-95 deg. temps.
I was faster on my old Bridgestones (S-03) which aren't quite as grippy but took a while to heat. It was a great time to work on preserving the car but I was letting everyone by

Brian

 

[LordDigital]

I’ve been autoX-ing for 5+ years and tracking for 2+.

Started with Eibach/Koni combo ,but my detailed current setup can be seen here. With the EDC computer my current setup is very streetable and the car feels great on the track (IMO is also fast on the timeAttacks ,but only when Kirk drives it :sarcasm: ).

My current setup gives me ability to adjust my alignment settings in nearly infinite range. I have access to Hunter DSP 4000 and I honestly don’t know how many different alignments settings I had on the car. My current alignment settings are here - these are more for track , for AutoX I would go with the slightly different rear toe.

I could talk a lot about the chassis setup on MA70 ,but I want to mention one setting that made the most impact and is usually not discussed too much on the boards – you need a lot of front camber to be fast on any kind of track or AutoX. My own temperature analyses on the front tires have shown me anywhere between 10 and 15 degrees Celsius delta when I used to run the maximum camber with the stock UPCs (don’t remember but it was around -1). I had to go to an extreme of shortening the stock UPCs as seen here ,but eventually replaced them with fully adjustable arms (camber AND caster). The temperature difference between inner and outer tire board have decreased to low single digits with -2.9 camber and is even lower with mu current -3.3. Again this is on UN-CAGED car with street tires ,for properly caged car on slicks such as Kirk’s supra (which is the fastest track MK3 to the best of my knowledge) you could live with a higher camber however it does not take more than quick flash back to group-A cars to realize that they were running even lower than -3 camber. And one more note in regards to aggressive camber and street car ,you have to be ready for it! The underSteer would be just gone and the car gets more into natural to overSteer behavior ,if you do not have experience on the track handling this don’t even try to drive it like that on the street!

As far as engine goes ,I went true stock 7m ,build 7m ,cammed 1JZ with GT35R and finally upgraded it to 1.5JZ.

Brakes are JDK BBK front and MKIV rear BBK ,but event with the stock rear brakes I never had any problems at events as extreme as MVP track days (150 track miles per event ,30+min sessions) or even TimeAttacks.

Last but not least drivetrain ,I started with the 3.7? ,then the 3.9? rear ends but it was always a struggle on the slow ChicagoLand AutoX events ,I finally got the JZA/MA 4.1x hybrid diff - pity that on my last autoX even tough I managed to get 4th BTD ,an $2008 Honda CRX was faster than me ,thus I decided to officially gave up on AutoXing the MA70...