Best - Simplest way to fix the Supra for tracking?

[s.hammi]

I am late to the party on the Mk 5 Supra. I purchased a 2026 at the beginning of the summer. I have tracked it a few times so far. Thompson in CT. and Palmer and MA. I noticed a few others in the forums also track in the Northeast. At Thompson, the Supra feels pretty good in stock form. A bit soft/ floaty at speed but manageable. At Palmer, it felt much more floaty, (sorry, best way I can describe it). There were times that it also felt like the rear of the car was disconnected from the rest of the car, making rear grip unpredictable. I am looking for the shortest/ simplest path to, at a minimum, solve the rear feeling disconnected to the rest of the car. Remove some of the floaty feeling. (Suspension? or Down force?) I am also looking for a suggestion for camber plates for the front. I would prefer not to completely ruin the car for road use, but I think I am going to have to sacrifice a bit of street-ability to feel a little more comfortable on track. Thanks in advance for any input.

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[freeform911]

try an alignment before changing parts..
sounds like rear toe might be out..

 

[Thraxbert]

Almost certainly rear toe. After alignment...

If still bad: diff brace

If still bad: traction arms

If still bad: adjustable toe arm

If still bad: I had a terrible time with certain tires, e.g. G-Force Rival S. The floaty/twitchy feeling didn't stop until I switched to another tire, even with all other possible culprits being correct + upgraded.

 

[s.hammi]

I did do the alignment recommended in these forums, (toe in front and rear), after my first day, and it did help some. I ran a Miata for 6 years so I am use to toe out. That doesn't feel like the issue.

 

[razorlab]

OEM tires or something else?

 

[Vegas17]

Start simple with tires and pressures. Even with a set of re71rz’s being a few pounds too low feels pretty bad.

 

[Hasan]

The OEM dampers are the issue. In normal mode the rear is too soft and in sport mode its too stiff. It never really matches the springs. The active damping is also very inconsistent. I would get a set of good coil overs.

The rear differential also moves around too much and a diff brace is a good fix.

 

[the_dude]

Start simple with tires and pressures. Even with a set of re71rz’s being a few pounds too low feels pretty bad.

curious, what hot pressures are you running?

 

[exe36m3]

What alignment specs are you running?
And the BMW rear toe is notorious for undoing itself.

 

[s.hammi]

The Dude - Stock Michelin Super sport. hot pressures - 34-36
exe36 m3- The Rear toe undoing itself does feel like one of the issues.
Hasan - Can the damper issue be undone with a change of the springs? Or are coil overs necessary?

 

[Vegas17]

curious, what hot pressures are you running?

I've been targeting 35psi hot. I had 275's on different wheels that i'd start at 26lbs but going to 18's and 295 square they didn't heat up as much so start at 28 now. They felt pretty soft/mushy even around 32 lbs after a few laps. I also had just finished hot laps in a RUSH SR so anything would feel soft after that.

 

[Hasan]

The Dude - Stock Michelin Super sport. hot pressures - 34-36
exe36 m3- The Rear toe undoing itself does feel like one of the issues.
Hasan - Can the damper issue be undone with a change of the springs? Or are coil overs necessary?

Ideally, you would want to match the damping with the springs. Changing springs should make a noticeable difference. In my opinion the springs are just a cosmetic upgrade to lower the car. Most of the people who track their cars eventually end up replacing the full coil over.

Another ex E36 M3 guy here

 

[SJ-Ray]

Can confirm what Hasan says.
Springs alone are just not harmonic with the dampers.
I got my Supra with H&R springs. It looked nice but never truly drove how i wanted it.
The switch to a KW3 V3 clubsport suspension was the right move.

 

[the_dude]

I've been targeting 35psi hot. I had 275's on different wheels that i'd start at 26lbs but going to 18's and 295 square they didn't heat up as much so start at 28 now. They felt pretty soft/mushy even around 32 lbs after a few laps. I also had just finished hot laps in a RUSH SR so anything would feel soft after that.

hmm... i ran stock sizes and targeted 30psi front and 26psi back. higher pressures felt like skates to me. i managed a 1:44.4 at club motorsports and 1:19.8 at thompson only after dropping to these pressures.

only modification to the car are camber plates. i'm running -3 deg on the front and -2 deg on the back.

i'm confused. what am i doing wrong?

 

[PaulFRDE]

I'm not sure what floaty means precisely, but in my case and particularly on tracks with elevation changes, I found adding sway bars a big improvements. It dies have an impact on comfort, but I still daily mine without issues at all.

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