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Discussion Starter #1
Hi all, just wondering if I can do any last minute adjustments to my suspension set up.
I have the Ksport Kontrol Pro, so far factory damping and lowered the car about 2"
Should I make the spring harder or damping harder? Brakes are stoptech and pads blue hawks.
Thank you
 

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Tires seem to be a big part of cone racing. whats the wheel/tire setup? you can play with pressures to dial in the the amount of grip at the limit.

I have Michelin Pilot Super Sports in 245/45/17 and they seem happy around 32 PSI hot.
 

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Discussion Starter #9
Hey so, ss595, not good at all🙈 I kind of knew, because those were my entry tires to get the car on the road after spending countless time and money, today temperature was around 85-90 I run 37psi wasn't eating up the tire walls, really no grip, and I'm a novice, but as soon as you do a chicane for example, you have no more grip for the next turn coming.
It was a fun day over all need to make the coilovers harder because i had tires rubbing at every runs, so I made adjustments as the day was going, I'm going to a track day in September and will NOT use those tires 🙂
Thank you all for you advises and this forum support.
Here is a few second of my last run taken by a friend
https://youtu.be/NR_flDjE38Q
 

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Discussion Starter #11
Of course I'm hooked! And yes understeer in every turns, is it fair to blame it on the tires? (I already did), the car will spin all 4 wheels in any condition under power (straight or turns)
 

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Of course I'm hooked! And yes understeer in every turns, is it fair to blame it on the tires? (I already did), the car will spin all 4 wheels in any condition under power (straight or turns)
I think some of it is inherent with a transverse TTV6, viscous coupler AWD, and how porky these cars are. Agreed with lawdog, it looks like rotation happens but i had push when the tires heated up and pressures got that high too.

My car had all of the steers! Oversteer on braking, neutral mid corner, and understeer on power that can snap back to oversteer again, depending on the corner. With the correct modulation it can be very effective if not over driven.
 

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I think some of it is inherent with a transverse TTV6, viscous coupler AWD, and how porky these cars are. Agreed with lawdog, it looks like rotation happens but i had push when the tires heated up and pressures got that high too.

My car had all of the steers! Oversteer on braking, neutral mid corner, and understeer on power that can snap back to oversteer again, depending on the corner. With the correct modulation it can be very effective if not over driven.

37 PSI is alot, on a warm day with some temp in the tires I usually try to maintain about 30-32 psi.. Also the 595SS suck for anything other then normal street use, but the 595 RSRR's are absolutely awesome on the track and auto cross, but surprisingly good in the rain too...

Something to keep in mind, tires will absolutely make or break these cars.. 275's is about perfect IMO for street car that see's moderate use.. I wouldn't recommend switching to RSRR's if you do alot of street driving, I feel a 245 is not near enough, especially if you have a subpar performing tire with some age on it - Try hitting up tire rack and looking in the 300 treadware summer tire range and through some width at it too, a 8.5" wheel can safely get away with a 255-275. 9" 275-295, so on so forth.

Being on Coilovers you also need Static Negative Camber up front... if you make the move to a 200Treadware, you're going to be wanting -3 to -4* up front... For the average 300 treadware summer, -2 to -3 is about the most you'll make use of before the tire lets go...

When it comes to Autocross with these cars, try avoiding being on the throttle any time other then corner exit, or straightline. It's ok to give some throttle to maintain speed in a corner, or keep the balance of the car, but as soon as you really try to accelerate in these cars, it will snowplow like a Porsche in a tight corner (especially on your tires)

My experiences with Ksports have not been great either....They are great when new, but seem to always leak/blow after about a year or 2 of use, so it may be worth giving them a good once over - if you have time, maybe even take the spring off and see if you compress the shock... If you can almost fully compress it by hand, it's probably going bad..

The last set of Ksports I tore down were 2.5 years old. all 4 were blown, 2 were bent, and just completely collapsed... They had seen nothing but normal street use.

all of that aside, I encourage you to to look into a Road Course event, these cars absolutely thrive on a open track with high speed corners... Tight and Technical is not their best game for sure..
 

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37 PSI is alot, on a warm day with some temp in the tires I usually try to maintain about 30-32 psi.. Also the 595SS suck for anything other then normal street use, but the 595 RSRR's are absolutely awesome on the track and auto cross, but surprisingly good in the rain too...

Something to keep in mind, tires will absolutely make or break these cars.. 275's is about perfect IMO for street car that see's moderate use.. I wouldn't recommend switching to RSRR's if you do alot of street driving, I feel a 245 is not near enough, especially if you have a subpar performing tire with some age on it - Try hitting up tire rack and looking in the 300 treadware summer tire range and through some width at it too, a 8.5" wheel can safely get away with a 255-275. 9" 275-295, so on so forth.

Being on Coilovers you also need Static Negative Camber up front... if you make the move to a 200Treadware, you're going to be wanting -3 to -4* up front... For the average 300 treadware summer, -2 to -3 is about the most you'll make use of before the tire lets go...

When it comes to Autocross with these cars, try avoiding being on the throttle any time other then corner exit, or straightline. It's ok to give some throttle to maintain speed in a corner, or keep the balance of the car, but as soon as you really try to accelerate in these cars, it will snowplow like a Porsche in a tight corner (especially on your tires)

My experiences with Ksports have not been great either....They are great when new, but seem to always leak/blow after about a year or 2 of use, so it may be worth giving them a good once over - if you have time, maybe even take the spring off and see if you compress the shock... If you can almost fully compress it by hand, it's probably going bad..

The last set of Ksports I tore down were 2.5 years old. all 4 were blown, 2 were bent, and just completely collapsed... They had seen nothing but normal street use.

all of that aside, I encourage you to to look into a Road Course event, these cars absolutely thrive on a open track with high speed corners... Tight and Technical is not their best game for sure..
Agreed. Found a sweet spot at 32PSI on 245/45/17 PSS at Pocono Raceway a few weeks ago. Thanks for clearing up the tire situation. Heard lots of good things about the RSRR from seasoned cone dodgers.

Negative front camber helps with turn-in. Was able to run about -2.5deg. with Tein S-Tech and ESC Struts in Sport.

I never cared to be competitive, Autox is just a great way to get aggressive seat time and find the lower speed limits of the car. Im sure you can be successful if you are willing to tune your setup to be most effective in that arena, but i quickly found out the compromises that would have to be made in setup are not worth it on my personal car. It way too good on the streets and back roads with a mild setup. My perspective is shifting to events like Track Night America and open track time. Also found out quickly that the work to seat time ratio at SCCA events is kinda lopsided. Seems like more value despite higher initial entry costs. ONE 20 min session is more driving that 2 days of autoX. Gotta keep working your way up.

That being said, I will do more SCCA events to stay sharp and keep refining setup and I recommend it to anyone who likes driving at all.
 

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Discussion Starter #15
Thank you both for your feedbacks, obviously you are both making important points. Would the 595RR's work for street use as well? I only use the car as a weekend car and may put 50miles or so, and will trailer it to a track when the time comes.
I'm going to a track day at Summit point WV in September.
 

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Thank you both for your feedbacks, obviously you are both making important points. Would the 595RR's work for street use as well? I only use the car as a weekend car and may put 50miles or so, and will trailer it to a track when the time comes.
I'm going to a track day at Summit point WV in September.
With that amount or driving I would go as aggressive as you can with tire compound. If you are in street class 200TW tires are fair game and opens up some options. Look at RE-71R, Rival S, etc. Here is a link with some good options.

https://www.reddit.com/r/Autocross/comments/ag3xqm/official_2019_rautocross_tire_compilation/
 

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I think some of it is inherent with a transverse TTV6, viscous coupler AWD, and how porky these cars are. Agreed with lawdog, it looks like rotation happens but i had push when the tires heated up and pressures got that high too.

My car had all of the steers! Oversteer on braking, neutral mid corner, and understeer on power that can snap back to oversteer again, depending on the corner. With the correct modulation it can be very effective if not over driven.
I've spent 13 years modifying my car to handle better on the track. The transverse TTV6 isn't the problem but the differentials are.

The Evo's are known for it's good handling has a very similar engine layout but much better diffs and we all know how they handle.

Among all the modifications I've done to my car (big brakes, Öhlins coilover, DR750 etc) I've replaced all 3 diffs on my car one by one and the car behaves completely different now.

The stock viscous center diff is too weak and too limited in it's ability to redistribute torque which make it unsuitable for track use. On winter road it may work fine with it's 45/55 torque distribution but when your putting the power down on the track if one axle starts to spin it will keep spinning because the viscous center diff is unable to transfer more than 50% of the torque to one axle.

So I started by installing a Supercar torsen center diff with it's 20/80 front/rear torque distribution and it really changes how the car behaves on tight tarmac tracks. The on throttle understeer heavily reduced and the car behaves much more like a rwd car. It also makes the behavior of the car much more consistent since the mechanical nature of the torsen diffs makes it much more predictable and faster in it's reaction compared to the stock viscous center diff.

Here is a video I made that shows how rear wheel biased the Supercar torsen center diff really is.


Even with the 80 of the torque going to the rear wheels I could still get the inner front tire to spin a bit when exiting tight corners as seen in the clip below. I cured that by installing a Quaife front diff which essentially removed all traces of on throttle understeer when used in combination with the Supercar torsen center diff. I ran that setup with great success at many events for a while.

When I upgraded to DR750's and water/meth injection I started having problems with the inner rear tire spinning wildly during acceleration out of some corners due to the weak stock rear LSD in our cars. Here is a video of that:


I ended up replacing the rear differential with a Mitsubishi torsen/visco hybrid diff that after a rebuild has worked great and the rear really stays planted now during acceleration.

Here is a video from an event a month ago that shows how the car drives now (fastest run is at the end).


As you can see the car tends always oversteer except in the really really tight breaking turns. During oversteer I can usually just keep the foot down and counter it easily which makes the car easy to drive on the edge for great lap times. However it doesn't always go as planned as you can see in the video above.

I run Öhlins coilover with SCE adapters on a very low ride height and 265 tires on 9,5 rims. I have 2.7° of camber in the front and 2° in the rear. The front camber is really important on these cars else you will eat up the outside of tires quickly and overheat the tires.

I've attached a few photos of how the car sits on the track.

I don't think the on throttle behavior of our cars can be changed significantly without replacing at least the center differential.
 

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I've spent 13 years modifying my car to handle better on the track. The transverse TTV6 isn't the problem but the differentials are.

The Evo's are known for it's good handling has a very similar engine layout but much better diffs and we all know how they handle.

Among all the modifications I've done to my car (big brakes, Öhlins coilover, DR750 etc) I've replaced all 3 diffs on my car one by one and the car behaves completely different now.

The stock viscous center diff is too weak and too limited in it's ability to redistribute torque which make it unsuitable for track use. On winter road it may work fine with it's 45/55 torque distribution but when your putting the power down on the track if one axle starts to spin it will keep spinning because the viscous center diff is unable to transfer more than 50% of the torque to one axle.

So I started by installing a Supercar torsen center diff with it's 20/80 front/rear torque distribution and it really changes how the car behaves on tight tarmac tracks. The on throttle understeer heavily reduced and the car behaves much more like a rwd car. It also makes the behavior of the car much more consistent since the mechanical nature of the torsen diffs makes it much more predictable and faster in it's reaction compared to the stock viscous center diff.

Here is a video I made that shows how rear wheel biased the Supercar torsen center diff really is.

https://www.youtube.com/watch?v=fTQEldXlCDc

Even with the 80 of the torque going to the rear wheels I could still get the inner front tire to spin a bit when exiting tight corners as seen in the clip below. I cured that by installing a Quaife front diff which essentially removed all traces of on throttle understeer when used in combination with the Supercar torsen center diff. I ran that setup with great success at many events for a while.

When I upgraded to DR750's and water/meth injection I started having problems with the inner rear tire spinning wildly during acceleration out of some corners due to the weak stock rear LSD in our cars. Here is a video of that:

https://www.youtube.com/watch?v=a0saF10a-94

I ended up replacing the rear differential with a Mitsubishi torsen/visco hybrid diff that after a rebuild has worked great and the rear really stays planted now during acceleration.

Here is a video from an event a month ago that shows how the car drives now (fastest run is at the end).

https://www.youtube.com/watch?v=9YTso_nYFv0

As you can see the car tends always oversteer except in the really really tight breaking turns. During oversteer I can usually just keep the foot down and counter it easily which makes the car easy to drive on the edge for great lap times. However it doesn't always go as planned as you can see in the video above.

I run Öhlins coilover with SCE adapters on a very low ride height and 265 tires on 9,5 rims. I have 2.7° of camber in the front and 2° in the rear. The front camber is really important on these cars else you will eat up the outside of tires quickly and overheat the tires.

I've attached a few photos of how the car sits on the track.

I don't think the on throttle behavior of our cars can be changed significantly without replacing at least the center differential.
Thanks for sharing, your setup is legit and I've spent hours combing through some of you posts here an on the other forum that cannot be named. Very impressive stuff.

To be honest the first time i saw the SCE Diff in the snow video I was pretty convinced that wouldn't be something I wanted to pursue. "How funny would it be to get stuck in an inch or so of snow in a AWD car?" I thought to myself and dismissed the idea. Then I did an autoX race and the light bulb blinked on. Its expensive and not the easiest modification to do but seems to be worth all of it for the return in performance.
 

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Thanks for sharing, your setup is legit and I've spent hours combing through some of you posts here an on the other forum that cannot be named. Very impressive stuff.

To be honest the first time i saw the SCE Diff in the snow video I was pretty convinced that wouldn't be something I wanted to pursue. "How funny would it be to get stuck in an inch or so of snow in a AWD car?" I thought to myself and dismissed the idea. Then I did an autoX race and the light bulb blinked on. Its expensive and not the easiest modification to do but seems to be worth all of it for the return in performance.
Yea the SCE diff costs quite a bit and involes a lot of work to install. If I lived in the US I'd just remove the transmission and send it Rvenge performance and let him do the work. It's a bit risky to do it yourself without all of the required tools and shims.

I learned that the hard way after spending a small fortune on various tools in order to be able to properly dismantle and assemble these transmissions.

But still it's among the best mods I've done to the car and more people here in Sweden are installing them now after seeing how they affect the handling.
 

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your videos and explainations are great unlogic!

would the AWD system in our car perform better in autocross if the front diff were LSD like the rear? Or is really the front/rear torque split that needs to be addressed?
 
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