longboarder

So my driver side rear Cup2 tire has a slow leak - about 1-2 psi per day and settles around 24psi. There is nothing in the tire like a nail or other piece of metal causing the leak. It's just leaking slowly.


So....I'm going to a track day at Auto Club Speedway this weekend which is a pretty high speed track. The configuration uses half of the "Roval" (think Nascar) where a GT3 can sustain 150 mph. Am I being naïve for thinking about doing a track day at ACS with such a leak?


Thx.

Apex-Monkey

Have you checked your wheel for any damaged, maybe you have a small bend ? Personally I would rather be more on the cautious side when it comes to tracking, why not replace the tire? Good luck and have fun this weekend

longboarder

I didn't even think about the wheel. Great point. I just contacted GMG to see if they can get me in tomorrow to check it out. Fingers crossed.

Archimedes

I would never go on the track like that, but that's just me.

Buteo

no track day with an undiagnosed tire issue-especially high speed track.

robmypro

Not on a bet.

DMoore

DO NOT DO IT.

I run frequently at ACS, including with Speed Ventures. (I'm not going this weekend, though. Too darned hot!) In my GT3, similar to yours, I'm going into turn 1 at ~150 mph. If you're losing air - and don't have a nail - it might well be a slightly damaged rim or tire bead. Either could cause a sudden and dramatic problem under the g-forces on the banking. I've also had the same "slow leak" problem. With me, it was a slight break in the bead of a brand new PSC2. Installation error? Defective tire? Can't be sure, but the result was the same.

The Fontana track causes more stress on a car that any other track in the SoCal area. DO NOT go out there if you have ANY questions about the condition of your car.

And I say that as a person who may share the same track with you.

You have a problem with either the tire bead or the rim. Don't track it until you fix it.

DMoore
'15 GT3

zedcat

Another quick check to try is the valve stem- at the wheel and also the valve core. soapy water or even spit and watch for bubbles. Have had a loose/ leaking core a few times.

GrantG

Yep, and if it's not the valve then dunk the whole wheel/tire assembly in water (they have this facility at tire shops) and see where the bubbles are coming from...

longboarder

Thanks guys. Don't know why I was being so stupid.


Confirmed an apt at GMG tomorrow morning to diagnose and hopefully fix. If it can't be remedied I'll take my other track car.

aamersa

It really depends on your driving style. If you push the car hard and near to the limits, I would highly advise against it.

If you're just there to have fun much more so than you can on the street I would bet money that you would come out just fine.

robmypro

Smart move. Nothing like a blowout at 150mph to ruin your day.

robmypro

I would probably bet money you are right, too. But i wouldn't bet my life. And that is the wager being made here.

DMoore

Alan and Scotty will take good care of you there. Maybe it is as simple as a loose valve stem or bad core. If so, lucky you. But always, SAFETY FIRST for everybody's sake.

DMoore
'15 GT3

major dad

I'm interested to hear how this finishes, wondering where the air is leaking from.