Track tire hot pressures.

[Dave B]

I know that different tires and set ups require different pressures but was interested in starting a thread on this.

I am aware that using the pressure where the tire is fastest will likely decrease longevity.

I have tracked the OEM Contis, (would not recommend that) as well as Nitto NT-01s and Hankook RS4s. The Contis were run with stock alignment and needed at least 38 PSI. The Nittos and Hankooks were run with neg 2.6 front camber (and about neg 2 in the rear) but otherwise stock suspension. Fastest times with both were with hot temps in the 32-34 PSI range but with the RS4s there was at least an 8 PSI increase for the front tires from cold to hot during a lapping session and this leaves me with cold pressures at the front as low as 24 PSI.

For the time attack series I run in, you get one warm up , 3 hot and 1 cool down laps repeatedly during competition which means I may not see the full 8 lb increase in pressure.

So what have you folks found? I have a competition event coming up soon with new Falken RT660s and would really like to see where I should start.

Please post your tire brand, pressures both cold and hot, and any suspension mods.

Sponsored

 

[REDRAGN]

Time Attack specs...this was with ambient temp around mid 70s
Falken RT660 275/35/18
Cold F 25 R 27
Hot F 35 R 32
Swift springs, front camber joints and rear arms
Alignment: (caster is 7.6 now with Whiteline anti-lift)

 

[Dave B]

Wow, a 10 PSI increase on the fronts even with all that camber. How many laps in your time attack events? Any idea of which lap was your fastest? I know that tires like the Nanking CR-1 and Yoko A-052 tend to get slower after the first lap. I suspect the new Bridgestone may be similar. I hear that the Falkens may go a bit longer at peak performance. Meanwhile something like the Nitto NT-01s may perform much better later in a session (or at least as well as at the beginning) but don't ever achieve the all out grip of the other tires. Also, given their optimistic UTQG rating of 100, are not allowed in number of competitive series.

Also noted the huge difference in front to rear pressure increases.

 

[Austin@Wunderladen Racing]

It's an FK7 but on our car with the RT660s (255 front, 235 rear) I run them 26/29 cold. They usually end up around 32-33 hot all around. I've spent a lot of time talking with guys about the 660 and the general consensus seems to be around that area. The sidewall seems a fair bit stiffer than the like of an A052 so you can get away with lower pressures. Another thing to keep in mind is that sidewall stretch will affect the stiffness of the sidewall too.

 

[AlphaDigital]

For the last couple of track days Ive had, the RT660s started at about 30-31psi and ended at roughly 36-37psi hot after a 20 minute session.


Im going to try the Kumho V730s next because im interested in seeing how a more budget friendly tire does. Ive read a lot of good things about the 730s being more consistent and nicer for wear while sacrificing maybe a second off RT660s and Yoks. They also apparently have very stiff sidewalls to the point where people are running them as low as 29psi hot.

 

[Dave B]

I like the idea of stiff sidewalls as well as you may get away with less camber. I know the Yoko (and definitely Nanking copycat) need a ton of camber to work and even then the common complaint is steering vagueness.

Certainly the tires that do well for autocross are not going to last well for HPDE and may not be consistent enough to be good for time attack events.

On another point, I have heard of using pressures as low as 30 hot on Hankook RS4s but that is on a light weight Miata so I wouldn't think that would work on a 3250-3350 lb CTR and driver combo.

 

[AlphaDigital]

I think for time attack, using yoks and CRS tires is acceptable as long as you know you probably are going to need to toss a cool down lap in there at some point.

I think the peak performance of the A052s (maybe the CR-S) are within the first 3-4 laps before they end up falling off. But most drivers just need a warm up lap and can probably full send right afterwards and get a PB.

I follow a lot of the gridlife stuff, and for their track battle events I think a fair amount of people are on Yoks. the GLTC is sponsored by Falken, so every competitor in that class is running RT660s though.

 

[Austin@Wunderladen Racing]

Yea A052 and CRS are still the top two for time attack but they both have a pretty decent premium, granted the 660 isn't the bargain it was last year either. I mainly run the 660 because it's a spec tire for the class.

I do plan to move to something cheaper that lasts longer for open track days and testing.

 

[DPL8]

32F H 34R H

 

[Dave B]

32F H 34R H

Which tire? Camber?

 

[AlphaDigital]

Yea A052 and CRS are still the top two for time attack but they both have a pretty decent premium, granted the 660 isn't the bargain it was last year either. I mainly run the 660 because it's a spec tire for the class.

I do plan to move to something cheaper that lasts longer for open track days and testing.

I think the 660 and the CRS is a bargain compared to the A052, arent they at least a couple hundred cheaper?

I plan to pull the trigger on a set of CRS tires next year just so I can try them out!


I was recently at an event with Dana Basinski who drives a K swapped FRS, and for what its worth he posted that he was really happy with the V730 because of how quick and how long they lasted for him. And if youre familiar with him you know how quick he is.

 

[DPL8]

I think the 660 and the CRS is a bargain compared to the A052, arent they at least a couple hundred cheaper?

I plan to pull the trigger on a set of CRS tires next year just so I can try them out!


I was recently at an event with Dana Basinski who drives a K swapped FRS, and for what its worth he posted that he was really happy with the V730 because of how quick and how long they lasted for him. And if youre familiar with him you know how quick he is.

I like my CRS tires been using them for a few years now, they have a preety steep drop off after 2-3 hard laps.

 

[Austin@Wunderladen Racing]

I think the 660 and the CRS is a bargain compared to the A052, arent they at least a couple hundred cheaper?

I plan to pull the trigger on a set of CRS tires next year just so I can try them out!


I was recently at an event with Dana Basinski who drives a K swapped FRS, and for what its worth he posted that he was really happy with the V730 because of how quick and how long they lasted for him. And if youre familiar with him you know how quick he is.

Yea A052 is a good amount more. It's been a minute since I looked at the CRS but I remember when it was called the CR1 it wasn't far off the price of the A052.

Yea Dana is definitely quick, I have the pleasure of competing against him in our FK7 lol. I'll likely go with something 100TW like an RC1 or NT01 for testing and open track days. Its super nice having tires that don't fall off and you can get repeatable performance with.

 

[Code Monkey]

Get a needle tire pyrometer and you will never have to guess.

 

[AlphaDigital]

Yea A052 is a good amount more. It's been a minute since I looked at the CRS but I remember when it was called the CR1 it wasn't far off the price of the A052.

Yea Dana is definitely quick, I have the pleasure of competing against him in our FK7 lol. I'll likely go with something 100TW like an RC1 or NT01 for testing and open track days. Its super nice having tires that don't fall off and you can get repeatable performance with.

whats the wear rate like on those 100aa tires? Is the consistency in laps worth the tradeoff for tire life and costs?

Would the RS4 suit you better? or is it not fast enough?

I was kicking around the idea of buying a set of Federal FZ201 just for shiggles to see how they are since theyre reasonably priced. Or even the Nankang AR1.

Tires are kind of like shoes for me, I like trying different ones and having multiple sets.

Sponsored