jcmbird

Need help with cold pressure for nitto 555rII's for track event .Whats the deal with nitrogen filled tires does it help at track thanks

ICaughtVetteFever

meldog21

I called Nitto and was told 38 hot. Depending on the track and outside temps your cold pressure will be different to end up with the hot pressure. When I check my tires the day after an event they are usually 27-31, so that would probably be a reasonable starting point for a cold pressure.

Keep in mind that everyone has an opinion on what they like as a hot temp.

Dog

vms4evr

Agreed. I ran mine with the target goal of 38/36 hot. I like the rears a couple of lbs lower. Once they hit 40 or higher they get greasy. I was starting 32-34 cold for the 1st session in the morning. Then bleeding off whatever it takes to get them down to 38 hot. Check them just as soon as you come off the track or pull in mid-session and check them in pit lane.

With the 38 hot it's also enough to get around outside edge wear. They are fine on camber challenged cars and lasted me about 6 weekends. Flipped them after 3 weekends.

MungoZ06

New Nittos; only one session generating heat (then three in the rain), and had similar settings/results.
By "flipping", do you mean re-mounting them so that ""outside", is on inside, e.g., right side tires and left side tires re-mounted with "outside" inside?

vms4evr

Yes exactly! It'll cost you some money to pay for another mount/balance. But based on the cost of these track tires I think it's worth it. After 3 weekends you can see the abuse on the outside edge compared to the inside.

Once they got down to the wear bar (roughly 2/32) I just moved the wheels from left/right side of the car. The grooves are almost gone and it seems to make no difference which direction they are running in since they are pretty much slicks and only have a weekend or two left.

Watch your rear tire wear. It is probably the driver and not getting air pressure right. Plus sliding the car in some turns. The rears wore out in the middle faster than the edges. So you see the tread blocks and grooves on the edges and the middle looks slick. That's why I changed to running the rears a couple of pounds lower. Didn't have any problems getting the fronts set right.

jcmbird

thanks ,someone mentioned nitrogen filled tires hype or help? 4vr those are the nicest red pants ever or is that paint?

LS6Vette02

Are these tires R compound?

96GS#007

Quasi. Softer compound than street tires like the BF Goodrich KD but harder than Hoosier or Kumho track tires. IIRC, the treadware rating is 100 (BFG are ~200 and the Hoosiers are ~40)

The original poster asked about nitrogen. My 2 cents...
The idea behind nitrogen is that your tire pressure will not vary as much because there's no moisture in it versus just filling the tire with air. It's also supposed to be better for tire life. Having said all that, unless you're racing professionally it's not worth it IMO.

A Google search of "nitrogen filled tires" turned up 375,000+ results for your reading pleasure

bobmoore2

Normal air is about 80% nitrogen, about 20% oxygen, and the rest is trace gases and a little water vapor.

If you're a professional racing team with an unlimited budget, then maybe nitrogen filled tires will provide a barely noticeable benefit. Otherwise, save your time and money for more usefull things.

67 fastback

nitrogen is something like 13% humidity.

one day racing karts @ Las Vegas Kart track, it was 9% humidity..drier than nitrogen and people where still purging their tires of air!

varkwso

Nitrogen has been discussed here a few times - go to the search function. If you can get "dry" ambient air you are about as well off. But it is definitely not worth it for a set of RIIs.

It is about 99% hype (and profit margin)...

dorikin_86

I've heard a few guys running 40psi hot on all 4 corners -

air pressure is really just personal preference...as long as the tire is not rolling over to the sidewall then you should be fine.

yakisoba

Nitrogen: Since alot of motorsports is about predictability, nitrogen makes sense for race teams. With a constant humidity inside the tire, pressure will build in a more predictable way, which translates to better (more consistent) pyrometer readings for the crew to fuss over. If you're not taking pyrometer readings, and set your pressure like most of us do (try a run at known pressure, then adjust based on tire temps), I don't see the need to run nitrogen. If I had the chance to do it for no charge, I'd try it just to see how the numbers changed. My 2 cents.