Tire pressures at the Track

[mystican]

What tire pressure are you guys running at the track?...I have the Toyos Proxes RA 1 on stock OEM 15/16 rims...

As I did with the oversteering thread...trying to find out the correct settings to produce a tad of oversteer in the turns...

thanks

 

[freelance201]

I run the RA1 on the track too.
You should target at about 38-40 psi hot.
Usually, I would set front and back at 30 psi, test it on the track, and adjust the tire pressure according to your own preference and your suspension modifications.
My set up is usually 30 psi front and 33 psi back (I have tein RA).
hope this helps!!

 

[freelance201]

and yes, if you want more oversteer, just raise the rear pressure 1 psi at a time, and test it.....but make sure that the psi for front and back should fall between high 30s to low 40s when hot.
And if you have adjustable suspension, make the rear stiffer than the front, this should also give you more oversteer.

 

[mystican]

Thanks for your help...

I have running the OEM pressures at the track with the Toyo RA 1...big mistake according to others...my hot pressures were running 50 in the rear and 42 in the front!!!!!!!!!!!

Maybe that is why I was pushing!!!

Interesting...my sidewalls were scrubbing right at the " vertical wear indicator arrow"

 

[docjohn]

At those pressures your ra1's were not working optimaly. get them at 38 hot max and then play from there.

 

[freelance201]

yeah, 42 front and 50 rear is wayyyyy to high
Also, depends on the temperature of the track, you might want to set pressure a lot lower than the one I mentioned.

 

[TigerNSX]

I ran 40/40 cold throughout the entire track season last year because of a wrong advice that I had gotten from my very first instrutor from BMWCCA.

No wonder I had frequent spinouts. :frown:

 

[2slow2speed]

What tire pressure are you guys running at the track?...I have the Toyos Proxes RA 1 on stock OEM 15/16 rims...

As I did with the oversteering thread...trying to find out the correct settings to produce a tad of oversteer in the turns...

thanks

BTW: It depends on the driving style, there are 2 ways to induce oversteer: power-oversteer or lift throttle oversteer. Lift throttle oversteer can be useful on slow corners where you want the NSX to rotate quickly. Power oversteer in general will make your laptimes higher because you are actually not putting down the power to the ground.

One more thing, RA1's like to run with lot's of negative camber, so you might want to keep that in mind given that you mentioned scrubbing on the arrows on the sidewalls.

On my NSX I run -ve 1.5 degrees up front and -ve 2.2 degrees on the rears, tire pressures 36/38 hot when I get to use the RA1's, for reference I run the SO3's at 38/40 or 40/42 hot.

Ken

 

[2slow2speed]

depends on the temperature of the track, you might want to set pressure a lot lower than the one I mentioned.

Huh? On cold days I need to start with higher cold tire pressures so that my hot pressures are kept constant.

You might want to double check on starting with lower tire pressures on cold days, it sure sounds counterintuitive to me..

Ken

 

[freelance201]

TigerNSX, its pretty suprising that your instructor told you to use 40/40 setup......very big mistake considering the R compound tires are a lot hotter compare to street tires during race conditions......dangerous stuff.....the tires probably felt like baloons!!

 

[freelance201]

sorry, didn't know if you were running r compound or not, but 40/40 is still pretty high.

 

[CCMDoc]

I ran 40/40 cold throughout the entire track season last year because of a wrong advice that I had gotten from my very first instrutor from BMWCCA.

No wonder I had frequent spinouts. :frown:

Boston Chapter? I got similar advice when I started HPDE about 4 -years ago. Well, that advice (running pressures higher than you would otherwise) comes from the belief that novices a) never hit speeds that heat the tires up that much; and b) higher inflation pressures "save" the tires and novices have been known to get upset with the "unexpected" wear on their new, expensive shoes.
Pyrometers are relatively inexpensive and the most difficult part of using one is finding someone to do and record the 4-wheel readings quickly enough when you pit (if you wait until the run is over or try to do it yourself, might not get as accurate info as otherwise).

If we get to the track together at LRP, NHIS or WGI, I'll be happy to pyro your tires while there (even if we are in the same run group).

 

[nsxtasy]

that advice (running pressures higher than you would otherwise) comes from the belief that novices a) never hit speeds that heat the tires up that much; and b) higher inflation pressures "save" the tires and novices have been known to get upset with the "unexpected" wear on their new, expensive shoes.

We can only speculate, but I would add as a source of that advice c) lack of familiarity with the NSX or its super-sticky OEM tires and factory setup and recommendations that are already made with an eye towards racetrack performance.