lobsterroboto

The ones that don't complain about how shitty super sports are, aren't fast yet.




Op for 90% track you should really really really consider not using the ridiculous 19/20 OE wheel sizes.


Have a set of track wheels with DOT R compounds like NT01 or R888R so you can drive home on them and change wheels when you get home.

village idiot

Agreed 100%. The problem is also consistency. On street tires, lap 1 is okay, lap 2 is great, lap 3 is maybe passable and lap 4 is greasy and lap 5 you're just wasting rubber, quickly. Every lap, you'll have different markers and corner speeds.

daleong

My plan for upgrading tires is to buy a set of 18/19" wheels and put R888R's on them or something similar.

blueray16

Thanks for the dose of reality. Just what I expected. The tire calculator is really neat.

Unfortunately, I already have a set of OEM wheels in the garage for well over a year now. I had an opportunity to get a full set of take offs for $200 shortly after i got my Z51 and jumped on it without taking the time to fully think it through.
Had i waited and pondered a bit more, i'd go with a square set up with NT01's and an AP Racing BBK.
I've dialed back my track schedule over the last few years. Will likely do just two events/ year.
Watkins Glen each spring and one other in the fall with a long 2 week road trip each summer. So will make due with the stock wheels I already have with the 245/285 Toyos and call it all good.

I've been down that very slippery slope with my Mustang. No desire to go there again with the Vette... but the temptation is always there!

X25

It's never too late. You can always sell the OEM set for a good value, and buy something decent for yourself.

If you don't have much of a budget, TSW Interlago wheels at 18x10.5 ET65 for all 4 corners comes to mind.

lobsterroboto

those are pretty much impossible to find any more.


They're pretty much the best bet up until you CCW, forge line etc.



Op, usedracingtires.com sells 5/32nd PSS tires in Z51 sizes frequently. I used them extensively until I got 18" wheels.

adriankapl

any one run sumitomo hertz 3 summer tires on corvette?

BrunoTheMellow

R888r , 255/35/18 and 295/30/19 on 14,15 base model wheels is what I run now. I like it. Any more grip and the suspension can't really handle it. Got the wheels from here for $300 a set shipped with tpms. Can't say no to that deal.

village idiot

I disagree. They have way less grip than SC2. They're basically a slightly more grippy PSS that won't overheat.

BrunoTheMellow

This is z51 suspension we are talking about. Much softer springs. Not setup for sc2.
​​​

X25

The springs were indeed a very limiting factor for me when I had the stock suspension, which was clearly illustrated by 315/325 Nitto NT01s turning the car into a boat. Swapping to a coilover setup with much stiffer springs was enough to drop 6 seconds off a 2-minute local track and get to the ballpark of what Grand Sport owners can do.

Fun fact, without the suspension upgrade, my friend with his 2017 1LE had no issue keeping up with me, despite the much heavier weight, showing how much stock suspension limits the Z51.

BrunoTheMellow

I wonder if swapping in GS leaf springs would be cost effective. Also the 1le has a **** ton more tire than a stock z51. That's their strong suit.

X25

I'd honestly be rather interested in Z06/Z07 springs, which are much stiffer up front, and would be a better fit for 315 front tires. With those springs, you can combine them with Penskes (shocks only), and since they would not be coilovers at that point, you'd also have zero clearance issues! Just a thought : )

village idiot

If you have MagRide you may not need the shocks. Also, unless you're running slicks, I think the GS springs would be better. Z06 is too stiff from what I've heard.

BrunoTheMellow

GS and z06 springs are the same. Also now that I think of it, it would be much better just to upgrade my sway bars.

X25

They're not same. GS front spring stays same for all GS models, and is much softer than Z06/Z07 if you go with Z07 option. Rears are upgraded to Z06/Z07 springs if you go with Z07 option.

I would personally prefer the stifffer springs, especially if using 315 front tires are in the cards.

DSC also has limitations in that it can only provide dynamic spring help, not static.

Some old discussion on spring rates in my build thread:
https://www.corvetteforum.com/forums...post1593554198

BrunoTheMellow

so yes. they are. unless you get the z07 package.

C6_Racer_X

The only advice I'd have for anyone tracking their car on new tires is, make absolutely certain you've got 5/32 or less tread depth.

Most "track" tires or "competition" (R compound) tires are molded at 6/32 or less, and with the larger tread blocks, they can be run as "sticker tires" (mounted, balanced, no further preparation).

"Street tires" including some of the "street category autocross tires" with 200 treadwear ratings will overheat if you run them at full tread depth (usually 8/32" or deeper). Shaving them to 5/32" before running them on the track will give you much longer tire life on the track and better handling. If you run them at full tread depth and you aren't feathering the edges of the tread blocks and pulling them off in chunks, you need to drive faster. But shave the tires first.

village idiot

I have a set of PFADT sway bars sitting in my garage.

I just had even wear on Cup2 and R888R so I didn't jack with it.