CT4-V What Tires

[Mbar]

Is there an echo in here?

LOL! totally missed your post

 

[StuckeyGR]

It surprises me that the fronts wear out a lot faster specifically on the 4BW rather than the rears since it's a high powered RWD car. I guess the braking forces generated on the front tires just chew through the rubber. On a good note though, 255 V730 Kuhmos are cheap. It could be worse. The fronts could be 285s, 295s, 305s,... etc.

I wish we could fit a wider front tire, 255 seems a bit small for a car of this size, especially with M2s and M3s running 275s.
And it would be a lot of fun to drive on track in a way that wears through the rears more quickly than the fronts, but most track day organizers frown on that .
This is the first car I’ve tracked with a staggered tire setup, and since you can’t rotate front to rear I guess I just need to get used to replacing front tires more regularly. I imagine I’ll be close to 2 sets of fronts for 1 set of rears as someone else here mentioned.
I talked to one of the tech guys at Tire Rack and he was also surprised I only got 3 track days out of these. I ordered a new set of front V730s and I’m having Tire Rack heat cycle them, so we’ll see if that makes any difference?

 

[Mbar]

I wish we could fit a wider front tire, 255 seems a bit small for a car of this size, especially with M2s and M3s running 275s.
And it would be a lot of fun to drive on track in a way that wears through the rears more quickly than the fronts, but most track day organizers frown on that .
This is the first car I’ve tracked with a staggered tire setup, and since you can’t rotate front to rear I guess I just need to get used to replacing front tires more regularly. I imagine I’ll be close to 2 sets of fronts for 1 set of rears as someone else here mentioned.
I talked to one of the tech guys at Tire Rack and he was also surprised I only got 3 track days out of these. I ordered a new set of front V730s and I’m having Tire Rack heat cycle them, so we’ll see if that makes any difference?

Yup, tracked cars usually have their front tiers chewed up first. Mainly the outer shoulders. More front camber helps. My goal is 5-6 days for the fronts.

 

[poor-sha]

Never been to a HOD or HPDE event, but are there "vendors" there that would do things like track alignments, brake fluid flushes, etc at the track? Would be great if I could drive to the event, do the alignment and everything there, then undo it before I left, rather than having to trailer the car to the event or drive it 5 hours on track alignment.

You can try calling Quantum who is in the industrial park at VIR, but honestly I’d just do it somewhere local and leave it.

Don’t worry about the warranty. As long as you haven’t tuned the car and are running the recommended oil you’ll be fine. If you do money shift it’ll be logged and they will know that as part of the investigation (and deny the warranty replacement). GM is going to tell the dealership what to do on warranty coverage but you’ll be fine.

For reference, I blew the motor on my C8 at VIR. GM asked for the PDR data but covered it without any question. Another guy blew the motor in his at VIR two weeks prior and also had no issue. I used to drop my C7Z off at the dealer straight from the track, complete with track tires and numbers without issue

 

[FrankRizzo]

Got my OEM TPC Spec Michelins installed yesterday at Costco. They had the tires in 3 days, but it took almost 2 weeks for an install appointment. They did a great job IMO. No issues and all the techs are "Michelin Certified" with certificates and patches (what ever that means).

Also they did not use nitrogen and green valve stem caps, which was appreciated by my bronze wheels!

Fun part was that the fronts were more worn (to the bars) than the rears...so I left early for the appointment and evened out the wear on the way over...heh.

I'm going to send in the $90 spring mountain rebate form and see how it goes.

Total miles was 9200 with one track day, my commute takes me thru Mulholland/Santa Monica mountains.

 

[Head Hunter]

Only got 9200 miles from them? Wow! Must've been one rough track day?

 

[Jim2000]

9,200 miles on a set of tires. You must be driving to the limit. That is what the car is made for.

 

[TheShark]

Re which tire - TPC or the standard PS4S... just back from Spring Mountain and they said all of their BWs run the standard 4Ss

 

[FrankRizzo]

Like I said about - TPC Spec.

I drive the canyons of So. Calif to and from work.

 

[GoldGSF]

This might be unrelated to the topic. But would going to a wider wheel be better for wear and performance for our cars? Technically we can go up to 9.5 wide in the front and 10 in the back. These sizes can still safely support our factory tire sizes. I'm hoping someone with experience can chime on this.

 

[FrankRizzo]

I did that with an AMG Benz back in the day, the problem was that the aspect ratio was a little off, so the car went nuts with the stability control in the corners because the computer did not like what it saw.

I think that if the OD is the same, you should be OK - but have no experience on this car...

 

[jodakid69]

I have been gathering "data points" by attending track events this year with the CT4V-BW uisng the stock Michellin 4S tires.

My original OEM fronts lasted 3 track days and on my fourth day during the lunch break, I noted the chunking on the left front so I stopped. The first set was run on stock alignment.

The second set of front was just starting to chunk after the end of the second track day. I ran easy on the right-hand high speed turns on the third day and "nursed" then through the third day. The second set had alignment adjusted to -1.6 for the 2nd and 3rd day. However, the outdoor temps were much higher when I was running this set. I remember that during the April track days the temp reading was cold or cool for most of the sessions.

Neither of the two right fronts have chunked.

I am still good on the rear after 6 track days - graining but not worn out or chunking.

I talking to other drivers they noted that NJM Thunderbolt track have many more right turns than lefts and both Lthe NJMP Lightning and Thurnderbolt have long sweeping high speed right hand turns. Therefore, the wear on the left front tires make sense - Lighting has a "banked High-Speed" right hand turn into the front straight:
I was also told by other drivers that I probably will need about -4 on the fronts. The left front is taking the beating.

I am switching to TW200 tires on all four for my VIR weekend track days.

 

[Head Hunter]

I believe the TPC is just part of the noise cancellation setup that Cadillac has for the Blackwings. Tire compound, durability, traction, etc should be the same as the non-TPC

 

[PL69]

Matchs with my estimate/expectations of the OEM PS4S, I will also be switching to RT660 this week for my next two track days next week. Running -2.55 front camber adjusted at the knuckles since we found no slots on the shock towers and pins didn't budge even with a air hammer.

 

[jodakid69]

Hello PL69, I paid $1100 for the "suspension system" shock tower adjustment to be made. And I am still at -1.6. The dealer claimed that I need to purchase parts to gain additional camber. I keep hearing about a Knuckle adjustment, can you explain that process? Some other track folks stated that you need like -4 camber to run at NJMP.

 

[strohw]

Hello PL69, I paid $1100 for the "suspension system" shock tower adjustment to be made. And I am still at -1.6. The dealer claimed that I need to purchase parts to gain additional camber. I keep hearing about a Knuckle adjustment, can you explain that process? Some other track folks stated that you need like -4 camber to run at NJMP.

Our cars have the same adjustment as the Camaro. There is a hanger on the knuckle that allows roughly .5 degree of chamber adjustment. You can see the details in this video here:

I can do this myself with a floor jack in less than an hour. So if you have to pay someone to do this then don't let them book much more than that.

Also, you're probably closer to -2 degrees in the front right now. If they're showing -1.6 on the front after adjusting the strut tower then I'd take a guess that their alignment rack is a bit off.

 

[jodakid69]

Our cars have the same adjustment as the Camaro. There is a hanger on the knuckle that allows roughly .5 degree of chamber adjustment. You can see the details in this video here:

I can do this myself with a floor jack in less than an hour. So if you have to pay someone to do this then don't let them book much more than that.

Also, you're probably closer to -2 degrees in the front right now. If they're showing -1.6 on the front after adjusting the strut tower then I'd take a guess that their alignment rack is a bit off.

Sweet! Thanks for the information and the video link. I will be reviewing the process before I put on the new set of tires tomorrow.

 

[poor-sha]

I believe the TPC is just part of the noise cancellation setup that Cadillac has for the Blackwings. Tire compound, durability, traction, etc should be the same as the non-TPC

Only the TPC spec is going to have the specific compounds and construction to the Blackwing which is very different from the normal 4S. There are two TPC spec 4S though, one with and without the foam for noise cancellation.

 

[Head Hunter]

Only the TPC spec is going to have the specific compounds and construction to the Blackwing which is very different from the normal 4S. There are two TPC spec 4S though, one with and without the foam for noise cancellation.

Ah thanks for the correction, appreciate that

 

[Furinax]

Got my OEM TPC Spec Michelins installed yesterday at Costco. They had the tires in 3 days, but it took almost 2 weeks for an install appointment. They did a great job IMO. No issues and all the techs are "Michelin Certified" with certificates and patches (what ever that means).

Also they did not use nitrogen and green valve stem caps, which was appreciated by my bronze wheels!

Fun part was that the fronts were more worn (to the bars) than the rears...so I left early for the appointment and evened out the wear on the way over...heh.

I'm going to send in the $90 spring mountain rebate form and see how it goes.

Total miles was 9200 with one track day, my commute takes me thru Mulholland/Santa Monica mountains.

View attachment 20318

Costco did your tires? I'm surprised as my Costco as well as others that I've read didn't have the specs to put it on their lifts.

And why can't you run nitrogen with bronze wheels?