BaylorCorvette

I'm coming from a 2013 Camaro ZL1 that I road coursed frequently with a 305/30/19 square tire set up that I usually ran around 35-36 PSI HOT.

I now have a C7 Z51 Corvette that is bone stock except for brake lines and brake pads. I've done one track event so far and I tried running between 34-35 PSI HOT and the back end seemed very loose.

For reference I'm running 275/35/18 in the front and 305/30/19 in the back. Looking for suggestions on HOT tire pressure for the NT01's?

emptnest

Subscribed

SouthernSon

I have found tire pressures to really be co-dependent upon camber settings with street tires. One driver likes them toward the high side of thirties and someone else might drop below 30. Best solution is use a good pyrometer and get your camber dialed in before adjusting too much pressure. Be sure to use a hard wired probe. Then, simply tweak it a bit for feel when all the values are looking good.

Mugen1516

Subscribing as well.

From what I've searched, some are saying start at 28 psi cold and run 36-38 hot.

Silver -V-

I started at 30 psi cold on NT01's and chalked the tires, as they progressively heated, I adjusted to the track and ambient temps. On hot days with braking tracks, found they liked to start at 31 cold, 36 hot, on hot tight turning tracks, 32 cold, 35 hot. In the cold months, 32 cold both tracks, and 38 hot.

The ambient, the track temps and the type of track will all dictate your pressures. There is no one magic set point, you need to check the tires and temps as you come off track to see what really works. Carry a chalk/tire marker and run a few laps and adjust to the day and track you are running on. NT01's seem to run best all the way to the edge of the tread line. adjust your pressures to that. RE 71's seem to like a stiffer sidewall, and a couple more pounds of air. YMMV

BrianCunningham

needed to change my pressures when I changed my camber

REVHARD

I guess i'll be the odd ball here. I read all the reports of people saying they like it around 36psi hot so I ran about 6 hpde's like that. I can say I decided to play with air levels after some technical talk with a fellow racer which had much more knowledge with tire tech. I dropped all the way down to 30 psi HOT. I tend to keep the front 1 or 2 psi more than the rear depending on the day, so 32 front and 30 rear with 315/30/18 NT01 square. I run -2.1 camber upfront and -1.4 in rear (I have Delrin bushings btw). The tire temps were even across the tire after a 20 minute session and tire wear is excellent.

wtb-z

My experience as well. I am not so good at finding speed by changing tire pressures but low 30s felt distinctly faster than mid 30s on the 315/30/18 NT01s and the same alignment.

insertclevername

Also don't forget the width of tire on different widths of wheels will play a factor for ap settings. A stretched tire might need more ap, than a pinched tire.

Tire pressures will be unique to each setup. I always take the first part of my day getting readings across the tires, and making adjustments. Then once I find the best pressures, I just keep them there throughout the rest of the day.

OP
If you are feeling loose, determine if it's on entry, mid or exit. Loose on entry just flat stinks, and makes the car hard to feel good to drive fast. I like running on the high side of ap's to minimize the slip angle. The tires fall off faster, but come in faster and ultimate grip level may be lower.

Could also check the alignment.

BaylorCorvette

Admittedly I was running stock alignment. I will be going to Texas World Speedway this weekend and will be setting up the track alignment and play around with tire pressures.

Joshboody

I ran about 35F / 37R hot hitting not quite half way on the triangles.
275 square on 17x9.5.
2.1deg F and 0.9deg R camber gave me very even wear.

STANG KILLA SS

congrats on the new Stingray! that thing will be way quicker than the ZL1.

ill be there on the 16th and 17th.

BaylorCorvette

Thanks, yeah it should be. However the ZL1 was modified, about 175-200 rwhp more than the C7 and more aero. I'll be curious to see what I run with the C7. I know at Grandsport (1 mile tracK) I was a couple tenths quicker with the C7, but I expected that on such a small track.

383

Do you guys that probe temps have a buddy/crew do it on pit road or do you drive to the garages then hop out and do it yourselves?
I typically fly solo, so how long do I have before the readings become useless?

sccaGT1racer

The more time that passes the more useless tire temps become. When running aggressive camber settings even long straights can skew readings. Remember its just another tool and look at the tire wear also when making adjustments.

insertclevername

I'll do it on pit road for the first check and correction, then just check in the garage area to make small adj.

I like to run about 5 laps check, adj. then head right back out to run on the different ap setting.

Bill32

That will happen very.......very quickly.

If you could see the real time data acquisition , on track with 12 sensors, you'd see how fast things change.

The best way to get accurate temps is in the hot pit in the middle of a session. Yea, you can't do that solo.

The way to do it solo is to take the temps as soon as you pull into the paddock not waiting until you get to your pit.
And, if you want good readings, you can't put around on the cool down lap. You need to still push the tires in the corners to maintain some of the temps. You can do this while still cooling down the engine and drivetrain.

The outboard sections of the tread are closer to the sidewalls and cool down at a different rate then he center of the tread which is thinner.

I really don't use tire pressures much except as a reference point.
We keep tire temperature/pressure log books on the cars including track and ambient temps and adjust the pressures buy temps and driver input.

383

I usually use tire wear but by then its sometimes too late. Ill just have to partner up with some guys at a TNA or something and trade off. Ill do your temps and you do mine kinda thing

SouthernSon

This! Much better to get the readings immediately at pit-in as soon as you can maneuver the car out of the way. Have someone do it for you quickly, not enough time for you to get unstrapped and grab the pyrometer.

383

I need one of these