Nitro tire pressure

[Kreider1]

I have Nitto 315/35 ZR17 102W rear tires on my roadster mk4 with over 600hp. What tire pressure should I be running. Is 24 lbs to low

[Jeff Kleiner]

22

Jeff

[BEAR-AvHistory]

22/23 on mine

[steno]

Ditto on the Nittos!:)

[Railroad]

Gauge readings vary. Surprising you can feel 1 lb difference in these cars.

[Hellion]

Outside temperature also is a factor to consider. Since it's never going under 100 degrees during the day in my neck of the cactus, I run 24 lbs all the way around on my new set of Nittos. After a drive, they all rise to 27 lbs and that seems about right from the driving impression I get.

[GoDadGo]

22

Jeff

Ditto on the 22 lbs for both ends of the vehicle; however, please know that I'm running 245/45-17 up front with 285/40-17 inch tires on the rear.
I did a little burnout in my garage once and the contact patch was nearly perfect and very even.

[BEAR-AvHistory]

White shoe polish across the tread will let you see how much your gauge needs to read. Adjust air till you get even wear on the stripe with no roll under on the edges. Log the gauges reading & use the same one each time you check. Newer gauges seem to be more stable/reliable than the older ones.

https://cimg0.ibsrv.net/gimg/acurazine.com-vbulletin/850x566/80-front_c3239f5c4ccbc71c3090250ea392112ded07a80e.jpg

[Avalanche325]

Which Nittos? The sidewall stiffness is different depending on what model you have.

I run 23 all around on NT05s based on chalk marking during autocross.

Sidewalk chalk comes off nice and easy.

[BEAR-AvHistory]

Which Nittos? The sidewall stiffness is different depending on what model you have.

I run 23 all around on NT05s based on chalk marking during autocross.

Sidewalk chalk comes off nice and easy.

You want a tire pressure that will give a flat footprint & not roll under. Tire in the picture is a 555R 315X35X17. Current tires are NT-01's. Will test them when I get some other work done.

Given that many gauges are inaccurate I run the stripes & then apply the gauge to get a number so I can repeat the stripe pressure using the indicated gauge pressure. Currently I have a number of gauges that read 22/23 & one thats a few pounds off.

[caesarmascetti]

I use 22

[Avalanche325]

Given that many gauges are inaccurate I run the stripes & then apply the gauge to get a number so I can repeat the stripe pressure using the indicated gauge pressure. Currently I have a number of gauges that read 22/23 & one thats a few pounds off.

The same as "A man with a watch knows what time it is. A mans with two is never really sure."

I had a Moroso analog gauge, it started losing repeatability after a year or so. I got a Longacre digital. It takes about $100 to get something decent enough for track use. I've chalked multiple times and always come to 23 on NT05s. Back when I ran Khumos, I ran 23 front 24 rear.

I would love to try a set of NT01s.

[Bob Cowan]

The theoretical advantage to nitrogen is that it does not expand when it gets hot. That means the pressure remains the same as the temps go up and down. That's why racers like it so much.

Most people recommend 22-24, with AIR. And that's the assumption that the pressure will increase as the tire gets hot. In theory, nitrogen will not do this.

Start with 24 psi. Drive the car enough to heat up the tires. Tires heat up faster with accelerating and braking, NOT with scrubbing. Then check tread temps or use chalk.

[swwebb]

The theoretical advantage to nitrogen is that it does not expand when it gets hot. That means the pressure remains the same as the temps go up and down. That's why racers like it so much.

Most people recommend 22-24, with AIR. And that's the assumption that the pressure will increase as the tire gets hot. In theory, nitrogen will not do this.

Start with 24 psi. Drive the car enough to heat up the tires. Tires heat up faster with accelerating and braking, NOT with scrubbing. Then check tread temps or use chalk.

?? In theory, nitrogen will not do this. ?? What theory is that!! All gas pressures increase with higher temperatures. Just saying. Sorry if you thought I was being a wise guy.

I believe the reason for nitrogen over air is the lower pressure loss due to permeation through rubber and the fact that moisture is not as much of an issue.

See https://www.tirerack.com/tires/tiretech/techpage.jsp?gclid=CjwKCAjwoNuGBhA8EiwAFxomA5OT-gzQNGUhfoZEsirGmYk66Tb5M6Uc6MLQsw0n3Vuwc1bmYf_ScBo CaIEQAvD_BwE&techid=191&ef_id=CjwKCAjwoNuGBhA8EiwAFxomA5OT-gzQNGUhfoZEsirGmYk66Tb5M6Uc6MLQsw0n3Vuwc1bmYf_ScBo CaIEQAvD_BwE:G:s&s_kwcid=AL!3756!3!386427243778!b!!g!!&gclsrc=aw.ds&&affiliate=HM5

[Bob Cowan]

https://nitrogen-generators.com/nascar-knows-nitrogen-in-tires/