To minimize understeer - tire or bar first
#1
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Is it possible to have too big a rear tire on a car? I have a 993TT and am using 315 R comp rears (the car came with 285). Is it possible the car would be faster around a track with narrower rear tires? I have a little more adjustment in the bars - I can go 1 holes softer in front and one hole stiffer in the rear. Which should I try first - bars or tires? I need new tires, is the reason for my question.
Greg H.
Greg H.
#4
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Sway bars are for fine tuning. You can use them to fix a handling issue, but that is a band-aid until you can fix it right.
It is possible to have too much tire for a car. However I am not about to say that is your problem because I don't know enough about you car.
It is possible to have too much tire for a car. However I am not about to say that is your problem because I don't know enough about you car.
#6
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I understand there are a lot of variables the most important probably being me. I was just trying to keep things simple. It's a dual purpose car, but the street driving mostly consists of driving to the track on the highway. I'm using Nitto NT01 245/315. Have Pss9 and TRG bars (which are relatively thick compared to what Porsche offers) I have a thread going on the 993 forum discussing alignment, but let me just say I am trying to align it to maximixe track performance. Camber at -2.3 in front which seems to work and -2.4 in the rear which I might lower based on wear and tire temps. -.15 total toe in front and +.5 total toe in rear (which seems a bit much to me).
Greg H.
Greg H.
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#9
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18" rims, 8 and 11
Not sure the temps are going to help. As was pointed out to me, the track i got the temps are is terrible for taking them because the tires aren't being stressed anywhere near the exit. The only thing of interest is that I'm getting the fronts up to 190 and the rears only up to 170 -175.
Greg H.
Not sure the temps are going to help. As was pointed out to me, the track i got the temps are is terrible for taking them because the tires aren't being stressed anywhere near the exit. The only thing of interest is that I'm getting the fronts up to 190 and the rears only up to 170 -175.
Greg H.
#10
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18" rims, 8 and 11
Not sure the temps are going to help. As was pointed out to me, the track i got the temps are is terrible for taking them because the tires aren't being stressed anywhere near the exit. The only thing of interest is that I'm getting the fronts up to 190 and the rears only up to 170 -175.
Greg H.
Not sure the temps are going to help. As was pointed out to me, the track i got the temps are is terrible for taking them because the tires aren't being stressed anywhere near the exit. The only thing of interest is that I'm getting the fronts up to 190 and the rears only up to 170 -175.
Greg H.
That tire temp distribution definitely points to understeer. Start with less rear toe in, go to 0 toe on the front or even a touch of toe out, and a bit more camber in front. See if that helps. Might need to do a spring change.
edit: I was misreading your toe settings, I think you already to have some toe out in front. So just go to a bit less toe in on the rear.
#12
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I understand there are a lot of variables the most important probably being me. I was just trying to keep things simple. It's a dual purpose car, but the street driving mostly consists of driving to the track on the highway. I'm using Nitto NT01 245/315. Have Pss9 and TRG bars (which are relatively thick compared to what Porsche offers) I have a thread going on the 993 forum discussing alignment, but let me just say I am trying to align it to maximixe track performance. Camber at -2.3 in front which seems to work and -2.4 in the rear which I might lower based on wear and tire temps. -.15 total toe in front and +.5 total toe in rear (which seems a bit much to me).
Greg H.
Greg H.
I would be concerned that you are using too much steering angle, which is causing the understeer and the higher temps. You might consider having someone ride along, or grabbing a ride in a car with someone who is versed in the NT-01. It's a different animal than a Hoosier R6 for sure.
-td
#15
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First thing I would do is get a good tire temp reading with Outside, Middle, Inside for all 4 corners.
Do you have adjustable shocks?