Track forum general chit chat.

[dparm]

Originally Posted by Ximian

Recheck alignment. A lot of it looks like heat stress.

This is what a heat stressed tire with sand fused to it looks like. Picture was taken after a track day and a long drive on the highway. The tire chunks didn't fall off, they just stayed on the surface and collected debris and cooled off. That's why it didn't come off with driving alone, the tires needed a good scrubbing as well.

Is heat stress another way of saying the tires are overheating?

My only other tire choice for this wheel is the Cup 2, which I already tried and burned through in about the same amount of time. Wasn't worth it so I went back to the MPSS.

Really trying to avoid dropping $5k on a set of Forgeline wheels and then tires on top of it...

[Ximian]

Originally Posted by dparm

Is heat stress another way of saying the tires are overheating?

My only other tire choice for this wheel is the Cup 2, which I already tried and burned through in about the same amount of time. Wasn't worth it so I went back to the MPSS.

Really trying to avoid dropping $5k on a set of Forgeline wheels and then tires on top of it...

Yes, heat stress describes the sometimes odd characteristics of tires after they are overheated and don't cool off slowly on a clean surface.

Both the MPSS and Cup 2s are road tires so they can handle only so many hot laps before overheating. A guideline I follow with road tires is a warm up lap, and then 2 hot laps followed by a cool down lap for the remainder of a session. It's not as fun as being able to push for the whole session but it saves a ton of money because I'm extending the life of the tires by at least a couple more track days.

Hankook Ventus V12 evo2 are great for doing odd things after being overheated. Also, I think they're a great track tire because they're half the price of the Michelins so you wont feel as bad destroying them.

[dparm]

Originally Posted by Ximian

Yes, heat stress describes the sometimes odd characteristics of tires after they are overheated and don't cool off slowly on a clean surface.

Both the MPSS and Cup 2s are road tires so they can handle only so many hot laps before overheating. A guideline I follow with road tires is a warm up lap, and then 2 hot laps followed by a cool down lap for the remainder of a session. It's not as fun as being able to push for the whole session but it saves a ton of money because I'm extending the life of the tires by at least a couple more track days.

It was definitely a hot day on Monday. Was in the 80s even in the early morning and was ~90 for the afternoon. Sun was out all day so the track itself was probably scorching hot.

What are other symptoms of tires overheating? I didn't notice any sort of traction problems. In fact, I ran a new PB.


I should probably clarify that these tires have 8 track hours on them plus a few thousand road miles. That's how long my first set lasted as well.

[Ximian]

For the road tires I've used, the speed they start squealing at gets lower after every lap. This is noticeable over several laps on the same turn. Also, it'll feel like you're slightly sliding while cornering as if there is a small layer of grease on the track or tires.

Depending on the tire compound and not having debris (chunks of tire, sand, dirt, fluids, etc) on the tire, it's also entirely possible to do very quick laps while they're overheating. The melting compound may provide better grip up to a point, but the tire will wear down quicker. If the track surface (or road to cool down area, paddock) isn't clean, debris will build up at different hotspots of the tire (as in the picture I posted) and that's when you'll start noticing grip/traction problems.

[bigjae1976]

8hrs is about normal for tires...about 6 days?

[M3 Number 86]

Originally Posted by roastbeef

He's the man. Might as well get your RB's done while you're at it.

He's not even in LA lolol

[dparm]

Originally Posted by bigjae1976

8hrs is about normal for tires...about 6 days?

Something like that. I had a few half day/afternoon-only events.

Like I said, the previous set lasted exactly that long too, but that was on a more street-focused alignment.

[M3MPH1S]

Originally Posted by dparm

Just noticed some unusual chunking/peeling (delaminating?) on the inside of the passenger front tire. In a few spots the cord is visible. I've never seen wear like this before on this exact tire. Car was just aligned to GM spec right after these were installed.

Driver front tire is not doing this. Rears are fine.

Tire Rack looked at the photos and said it's either something off in the alignment, or it could be a product of the track/driver inputs. They're claiming it isn't a defect.

Any ideas what's happening here? Should I have the dealer re-check the alignment?

Inside edge would imply a possible alignment error with toe would it not? (Among other possibilities) Just because they're a dealer doesn't mean they always get it right. My friend (370z) and I get our alignments done by a friend who works at a dealership, and one time 370z friend had abnormal wear and went to get the alignment checked at a different shop and they found the toe was way off. We never found the exact reason, but the dealership friend could only guess that the sensor wasn't lined up properly or had bugged out somehow.

Also, just curious, do the C7's use double wishbone or macpherson struts up front?

[dparm]

Originally Posted by M3MPH1S

Inside edge would imply a possible alignment error with toe would it not? (Among other possibilities) Just because they're a dealer doesn't mean they always get it right. My friend (370z) and I get our alignments done by a friend who works at a dealership, and one time 370z friend had abnormal wear and went to get the alignment checked at a different shop and they found the toe was way off. We never found the exact reason, but the dealership friend could only guess that the sensor wasn't lined up properly or had bugged out somehow.

Also, just curious, do the C7's use double wishbone or macpherson struts up front?

Front is double wishbone, yes. Chevy calls it "short/long arm". It's just a revised version of the C6 suspension.

https://www.edmunds.com/car-reviews/...alkaround.html

[M3MPH1S]

Originally Posted by dparm

Front is double wishbone, yes. Chevy calls it "short/long arm". It's just a revised version of the C6 suspension.

https://www.edmunds.com/car-reviews/...alkaround.html

TIL Corvettes still use leaf springs! Had no idea.

[dparm]

Originally Posted by M3MPH1S

TIL Corvettes still use leaf springs! Had no idea.

Yep, composite. People love to rag on the car for being an old-fashioned, low-tech, plastic boomer-mobile, but Chevy has stuck with things that work and has perfected it over the years.

[CorruptCommie]

No wonder the Camaro's are so much faster.

[M3MPH1S]

Cool article I found about the Corvette leaf spring setup

https://tech.corvettecentral.com/201...vers-vs-leafs/

I might be misunderstanding the explanation there, but the part about cross-talk/seesaw effect might partially explain your unusual tire wear

[roastbeef]

to be honest, i didn't realize they used leaf springs. very interesting and makes sense for how they implement the design.

[dparm]

Update: the dealer's Corvette tech who has done all the work on my car looked at the tires and said the wear looks appropriate/consistent with track usage. He seemed okay with the 8 hour lifespan given the car's performance potential and weight/size. He's a pretty no-BS guy so I don't think he was saying that just to avoid doing more work or whatever. He didn't have any specific comments on the flaking/peeling.

I drove 10 minutes to Fall-Line for a second opinion. Although they were busy fixing actual race cars, some eyebrows were raised as soon as I started mentioning the GM "competitive driving" alignment spec, especially with regards to toe. I think I'm going to have them replace the two front tires and realign it to something they feel is appropriate. They won't have the tool to adjust caster but I'm not that worried since it's still basically within spec and doesn't hugely contribute to tire wear (though it can slightly impact camber).


If this doesn't work, it might just be time to bite the bullet and get HREs or Forgelines. The popular setup is 18x11 front and 18x12.5 rears, with Rival S tires in 315/30R18 + 335/30R18. Hoosiers are also available in this size.

[inTgr8r]

Originally Posted by kpewpew

No clue myself on rebuildable or not. I called ECS Tuning and they quickly said ok, sent me an RMA form for return. I asked for a refund/credit so I can get the Dinan monoballs for future install. Shop said Dinan ones install in a much more secure manner

Sorry to hear about problems with the Turner monoballs.

FWIW I installed the BW monoballs this year.
I know its a small sample size, but I'm 7 track days and counting without issue.

[bigjae1976]

Originally Posted by roastbeef

to be honest, i didn't realize they used leaf springs. very interesting and makes sense for how they implement the design.

I think they started using the transverse leaf spring in the C6 Z06?

I also find it odd they would spec that much toe. That wear pattern usually indicates excessive toe with aggressive neg camber.

[kyippee]

Originally Posted by inTgr8r

Sorry to hear about problems with the Turner monoballs.

FWIW I installed the BW monoballs this year.
I know its a small sample size, but I'm 7 track days and counting without issue.

Good to hear - P-Tech did say BW and Dinan ones seem to install very securely and are worth looking into

[inTgr8r]

Originally Posted by kpewpew

Good to hear - P-Tech did say BW and Dinan ones seem to install very securely and are worth looking into

also of note,
On my Z4MC I ran BW monoballs on my RTABs for 3 years without issue.
Different application but the function is similar and the BW construction was very similar..

[roastbeef]

people seem to be all over the place with monoballs... i have fall line monoballs. they are very tight, basically press-in, but they have bolt-in construction. its been a few years and i have been very happy with them.

[dparm]

Originally Posted by roastbeef

people seem to be all over the place with monoballs... i have fall line monoballs. they are very tight, basically press-in, but they have bolt-in construction. its been a few years and i have been very happy with them.

I was going to ask if Fall-Line made anything....

[roastbeef]

Originally Posted by dparm

I was going to ask if Fall-Line made anything....

.