Race Tracking Your Supra - Information exchange

[theQuaybee]

The best I can give you is this for now, though the video makes it not look as bad as it feels (it feels terrible and extremely unstable). I did some tests with my hands off the wheel to see what it did, and I need to export those video clips.

If you start at this timestamp and maybe slow down the playback speed you can kind of see it.

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[garudathree]

your kinematics need to be reviewed. double check your toe curve on both ends.
asymmetrical number of spacers on the LCA? rear traction links at different lengths? asymmetrical shock settings?

When was your last alignment?

 

[theQuaybee]

your kinematics need to be reviewed. double check your toe curve on both ends.
asymmetrical number of spacers on the LCA? rear traction links at different lengths? asymmetrical shock settings?

When was your last alignment?

I had an alignment adjustment a few days before the track day and another alignment check at the track from the shop there. Neither made a difference in this issue.

 

[razorlab]

Hi all, my turn to come to you with a problem (besides ongoing cooling issues). When I brake, even a medium amount, track or street, my entire car rotates to the right, every time. It also doesn't quite seem to be EXACLTY when I press the brakes, but almost after a split second. Honestly, it's very hard to pinpoint exactly what is happening. All I know for sure is, after I press the brakes, the car rotates right after the nose dives. But, once it "settles" during the braking, after it has rotated, it doesn't keep pulling to one side. It's like it settles in at that weird angle, and I just have to countersteer at a consistent angle during the braking zone.

I've changed brake pads back to OE, still the same. I'm still slightly suspicious of a caliper issue or something, but the car had 3500 miles on it when I bought it earlier this year, and this was my 4th track day. I also would expect the car to keep pulling to one side during the entire braking period if it were related to brakes, but that isn't really the case... again, best I can tell.

I've had alignment checked like 3 times and by different shops, I can say with confidence that it isn't related to alignment. Unless there's something everyone missed.

All my bolts look torqued via paint pen marks, but I haven't checked every single one. Things suspension-related I've changed myself are:

• Nitron R1 Coilovers
• SPL Front LCAs
• SPL Front Caster Bushings
• SPL Rear Traction Arms
• SPL Rear Toe Links
• AMS Front Sway Bar

Could it be something electronic? To me, to the best of my knowledge, it feels like something is maybe loose and shifting under braking, aka dynamic alignment. Thoughts are appreciated.

I've had this exact same issue and it was when I first started doing my own alignments at home and I really sucked at first. Just on the street as soon as I braked the car would want to swap ends. What are your current alignment settings?

Are you making sure your alignment guy is making sure the suspension is properly settled before doing the alignment?

 

[ABQautoxer]

I had an alignment adjustment a few days before the track day and another alignment check at the track from the shop there. Neither made a difference in this issue.

If it were me, I'd take a close look at that traction links that they are the same length. Alignments don't get kinematics like that, just camber and toe in the back. They can make a good alignment but if one side is shorter than the other, when the car goes into squat or rise, it will be asymmetrical left and right.

 

[Todday1]

I would also suggest looking at all the control arm bushings and bolts. If you are getting on the brakes and there is play in one of them it can cause the wheel to move slightly which then could pull in that direction. This could especially be true on the rubber ones that could be worn.

 

[Islindur]

@theQuaybee how do U like Nitron R1 compared to stock? Body roll etc?

 

[FLtrackdays]

I had an alignment adjustment a few days before the track day and another alignment check at the track from the shop there. Neither made a difference in this issue.

Can you post your last alignment? Toe makes a huge difference, even if they are doing it right. I played with mine in the beginning (like Bryan mentioned) and damn she did not like it. It wasn’t like in my previous car at all. Dumb statement but was exponential in this car. I had too much toe out (up front) and too much in (in the back) and braking from 140 mph down to 80 mph in a turn was ruthless.

Bryan and garudathree might even be able to tell from your alignment spec sheet. They do a ton of this stuff on their own. Some of the many great sources on this thread.

Back to your computer question. Unfortunately, like me, you‘ve got a lot of non OEM parts on the car. If any one of those are causing the car’s algorithm to detect a difference, yes the computer can start kicking in at the wrong time, if you don’t have both traction and VSC turned off. Some people prefer to track with one click only. Thus they have to keep her closer to factory alignment toe specs not to engage the VSC. Otherwise, the car may interpret your high speed turn as a slip and try to wheel correct (via brake, power cut, or both). None of it is fun on track if she’s not reading it right. For anyone interested on what Toyota calls it ?

 

[Islindur]

I was just at MSR-C on Friday with a fresh Texas Track Works alignment and was very happy with it. I can track down what I have if you need a comparison. I'm on HKS HAS, Millway camber plates and SPL adjustable caster bushings for reference.

street or uniball millway camber plates? Any additional noise vs stock?

 

[razorlab]

I bought these for fun lapping and not worrying about PB's. Ironically I used them yesterday at Palmer and I did a PB.

That said, I will never buy these again. They are SOOOOOO loud on the street. They low level vibrate the whole car and the hum is so loud I can barely hear the car downshift. The final nail in the coffin for me was the wear after basically one track day and driving to/from the track 2.25 hrs each way.

CRS are basically the same price, make no noise on the street and have more grip. Great example of treadwear numbers meaning nothing nowadays. 200tw faster than 100tw. I'm going to do another set of Kumho V730's instead of these for just fun lapping from now on.

 

[theQuaybee]

Can you post your last alignment? Toe makes a huge difference, even if they are doing it right. I played with mine in the beginning (like Bryan mentioned) and damn she did not like it.

Here you go. If something seems off, ask me, because I feel like they told me one of these numbers wasn't correct on the sheet. But it may be the caster that he wrote out (in which case the written number is correct)

In regard to electronics, I track with traction completely off. I still feel like you never know what the 2,000,000 sensors in the car are telling the e-lsd to do sometimes, though. It also still doesn't give me all the power coming out of corners all the time.

I was just at MSR-C on Friday with a fresh Texas Track Works alignment and was very happy with it. I can track down what I have if you need a comparison. I'm on HKS HAS, Millway camber plates and SPL adjustable caster bushings for reference.

Unfortunately, TTW is way too inconvenient for me. It's extremely difficult for me to work with their schedule and location. Great guys, though. Fifth Gear Autosports and Doghouse are very competent performance shops with knowledgeable guys as well.

 

[theQuaybee]

If it were me, I'd take a close look at that traction links that they are the same length.

I had the last guy triple check that, and he noticed that one wheel was slightly more forward than the other. He corrected it, but it didn't help the braking issue. Whether the traction links are actually the exact same, I'm unsure.

I've had this exact same issue and it was when I first started doing my own alignments at home and I really sucked at first. Just on the street as soon as I braked the car would want to swap ends. What are your current alignment settings?

Are you making sure your alignment guy is making sure the suspension is properly settled before doing the alignment?

See above. I'm new to trying to understand suspension so I can only go off the competence of the shops I take it to. With that said, the guys I take it to are pretty competent people, especially between the two different shops that have looked at it before last track day.

 

[theQuaybee]

You guys seem hell-bent on alignment so far, which I totally get. We don't think something could be loose? I think I'm going to do something rare for me and just leave it at the shop this week and have them figure it out. I've run clean out of motivation and fks.

 

[FLtrackdays]

Here you go. If something seems off, ask me, because I feel like they told me one of these numbers wasn't correct on the sheet. But it may be the caster that he wrote out (in which case the written number is correct)

In regard to electronics, I track with traction completely off. I still feel like you never know what the 2,000,000 sensors in the car are telling the e-lsd to do sometimes, though. It also still doesn't give me all the power coming out of corners all the time.

Unfortunately, TTW is way too inconvenient for me. It's extremely difficult for me to work with their schedule and location. Great guys, though. Fifth Gear Autosports and Doghouse are very competent performance shops with knowledgeable guys as well.

Okay here’s mine:

And…

Spec above (courtesy of Bryan from another page)

I know my car performed or felt off when my toe was off. The two go hand in hand pretty easily when you start messing with it. In the beginning my dash looked like a Christmas tree (steering angle sensor, you name it, while installing the SPL goodies). Last thing I needed to do at that point was messing with the alignment. Yet I did ?… I added too much toe out up front and more in on the back. Man she sucked on track! I’d definitely take your toe back in to spec (negative in the rear) and go neutral up front, until you can find someone that‘s fantastic with alignment with adjustable parts.

You are also right that it never hurts to check every bolt & any aftermarket part you’ve put on. Definitely may find something there as well.

I bought these for fun lapping and not worrying about PB's. Ironically I used them yesterday at Palmer and I did a PB.

That said, I will never buy these again. They are SOOOOOO loud on the street. They low level vibrate the whole car and the hum is so loud I can barely hear the car downshift. The final nail in the coffin for me was the wear after basically one track day and driving to/from the track 2.25 hrs each way.

CRS are basically the same price, make no noise on the street and have more grip. Great example of treadwear numbers meaning nothing nowadays. 200tw faster than 100tw. I'm going to do another set of Kumho V730's instead of these for just fun lapping from now on.

Damn I’m so glad I didn’t go that route and bought the CRS’s. Be interesting to see if you can get the same time in the CRS’s however ?

 

[theQuaybee]

My understanding is the rear toe is there to help counteract bump steer. I essentially copied a buddy’s specs in Austin that had his set similar/the same to Jackie D. He doesn’t have the problem I do.

I’ve had my alignment set this way without issue for at least one of my track days this year too, so I don’t think the issue is in the alignment setup. I also wouldn’t go off of official Toyota spec for a track setup. That spec is for the street and with OE suspension.

Btw I really appreciate all the feedback, it’s giving me more to check and confirm. I don't want to come off as dismissive. I’m going to try a couple more things myself maybe next weekend, and then send it away if they don’t help.

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