12zo

My '12 ZO6 is stock and new to me. One of my projects going forward is a set of track tires and wheels.

I want to run a DOT legal tire. No slicks and Hoosier info needed.

I have 9 years of DE experience and instruct for a few clubs. After 20,000 DE miles I can say I am very happy running track days on RComp tires and want to focus on how best to do that. After doing this for a while it is obvious to me that your tire budget at least doubles going to Hoosiers and for DE that is not where I need to be. I've seen 3x budget from Nittos to Hoosiers.

After searching around a lot here I still feel a bit confused. I do plan a call to my favorite wheel guy this week, John at CCW, and that will probably explain it all, but any feedback is appreciated.

Wheels:

First, it sounds like 18's all around are preferred. Is there a definitive reason why on this car? Tire fitment? Wheel weight? Swapping wheels?

I can't find a single tire manufacturer that any combo up to 345 won't fit if I buy 11" fronts and 12" rears. Why do people buy rears in 13", or fronts in 12"?

Tires:
I've looked at every one I can think of, 888's, MPSC'S and Super Sports, Yoko A048's and Khumo V710's.

It sounds like Toyo's in 305/335 or 315/335 would be best for no rubbing and good grip. 315/345 may be even better but some report they rub with cooling ducts and ONLY Khumo V710's sells those sizes.

I don't care if they rub at full lock, the car won't be there between the trailer and track.

I'm looking at the Toyo 888 in 305 or 315F and 335R or the Khumo V710 in 315F and 345R.

I know the Kumo's wear a lot faster. Just seems like options are limited so they are the only second choice I can find.

Bottom line: looks like Toyo 888' 305/335's on 11" and 12" wheels is a good choice. It's that or Kuhmo V710's 315/345 on 11/12" wheels.

Thanks for the feedback. Anyone selling CCW C-10 or 14's in 11/12" let me know.

jwebsta32

I'm going to be running 18x11 and 18x13 ,probably the 315, 345 set up. Why are you leaning towards 18x12 rear?

troyguitar

It seems weird to me that people run 10.5 or 11" wheels for 315 tires, then for 335 or 345 they want to move all the way up to 13" wheels. Do bigger wheels just not fit in the front?

Using 10.5 - 11.0" fronts for 315's is equal to running 11.2 - 12.0" rears with 335-345's.

Going the other way, using 13" rears for 345's is equal to running 11.9" fronts for 315's.

12zo

Why run a bigger wheel than needed? My question exactly.

11"F and 12"R you can mount all the tire options I can see using.

Probably not get many answers with the Super Bowl on....

skxf430

I am running 11/13 with a 295/335 R888 combo with no rubbing at full lock. My car is still a street car so I didn't want to run a wider front with the possibility of rubbing.

For my use, the R888's are really my only option at the moment unless Nitto comes out with a NT01 or Toyo with the RA1's. Otherwise, running Hoosiers or Kumho 710's are not really a viable alternative for the street.

12zo

The main questions are:

Why would anyone buy a 13" rear and what is the reason people track on 18's vs 18/19"???

Feedback on these two: Toyo 888' 305/335's on 11" and 12" wheels, or Kuhmo V710's 315/345 on 11/12" wheels???

BEZ06

Recently I've been running stock ZR1 wheels with the stock MPSC ZP (Zero Pressure runflats). These tires are a stock tire on the PDE optioned ZR1, and I believe on the Z06 Z07 Carbon. They are a fantastic tire on the track! And of course are street capable.

I've also run the stock ZR1 Michelin PS2 ZP, and they are great for a street tire.

If you want to run stock Z06 wheels, the Michelin PSS (Pilot Super Sport) is REALLY good!! They're available in stock Z06 sizes and I've run them and was really impressed!

Bob

Below is my Z06 with stock ZR1 wheels with MPSC ZP tires:








.

UrbanKnight

AS for why does everyone run 18", because the scrubs and "race" tires are plentiful.

When you up to the 19 and 20 rims, tire price goes way up...

You mentioned looking for Non R tires, but list the Kuhmo 710's, which I thought are R comp unless I am mistaken.

I run CCW 18's for my track use- and getting scrubs at 125-150 tire is actually cheaper to me then burning up PSS's......

mbeckers

Most of the folks running 18's are on full race slicks. You can buy used race slicks with a limited number of heat cycles on them for around $100 per tire. Almost all of these tires are 18's. It is an economical way for experienced drivers to run HPDE.

The width of the rear wheels is largely based on tire preference. I run 11's in front and 13's in the rear to get the widest tire patch that I can. I like to run michelin slicks because of their grip and longevity. The 13's allow me to run a 31/71 R18 in the rear.

troyguitar

Do 12" wide wheels just not fit in the front? They would help just as much as going to 13" in the rear.

12zo

Thanks for the responses. Btween those and speaking to John at CCW and understand the setup better now.

He says testing proved the 888 fit better on a 13" vs 12". The tire was more predictable and easier to manage what it needed. Basically, the tire sat on the road better on a 13" than a 12".
Up front he says run the 11" wheel.

He believes the correct tire choice is 295/335 for Toyo 888. Those tires most closely match the OE stagger and makes the computers happy.

I hear you guys on the scrubs. Maybe after I get used to the car I'll go there.
Thanks all.

db2xpert

Tried the 31/71 - I do better with 33/65's... but not always available.
I have a set of 31/71's with decent rubber if you're interested.

96solo

I agree with most of this. I don't run Toyos so no knowledge on them, but I have a lot of experience in both Kumhos and Hoosiers. The 295 or 315 front and the 335 rears have the same height and does not confuse the computer. 345 rears are 1/2" higher and may have been a help in a ABS failure and caused a spin for me. I find the 295's will cause push in slow speed tight corners and the 315's don't. All this on 18" CCW wheels and Speedlines. He's right about 11's in the front. If you have added LG brake coolers, you may get some rubbing on the coolers. It is close. He 's right on 13's as the straighter the sidewall the better the tire reacts. Cupping the sidewall in on a narrower 11 or 12 inch rim will not allow all the tread on the ground and could cause a possible loss of the bead.

345's Hoosiers will crack a stock fender on a transition or bouncing on curbing. I have L5 fenders to avoid that.

My choice is 18" wheels all the way around and 315 fronts and 335 rears, except in rain then smaller size is referred.

D.J. Covert
2008 NASA-AZ TTS Champion

skxf430

Do you get any rubbing from the 315 fronts at full lock?

12zo

I looked up the tires rotations per mile. There is more to it than that, like rubbing, understeer issues and how they sit on a rim etc, but the computer is looking at size and this is a good measure.

OE:

Goodyears

275/35-18 818 rev's
325/30-19 782 rev's

My initial interest was in 888's and Khumos, both 18" square:

888

295 828 rev's
315 814 rev's
335 799 rev's
No 345's

V710

305 814 rev's
315 790 rev's
No335's
345 778 rev's

Looking only at this data the Khumo 305/345 numbers are real close to OE. The Toyo numbers closest to OE are the 295/335 tires.

The "perfect" fit wheel for the Toyo is the 12" if you look at the Toyo factory spec numbers. What I get out of all this is that there is a lot more to this than just looking at numbers but at least one has to study what is going on.

CCW says the Toyo is easier to manage on a 13" rim. Good enough for me. They also report some computer issues with any Toyo front bigger than 295. The numbers bear that out. An 888 315 front moves away from the factory rolling distance relationship. So does the Khumo when you move up front to a 315. The tire rolls less per mile. Simple.

In all this one has to weigh how they like the car, the interest in dialing out under steer, rub, the effect of turning all driver modes off or at least Comp mode. Lot going on.

I'm going to be learning this car. My 20,000 track miles are erased, as far as I'm concerned. New car, new deal. I am pretty sure I'll start on 888's and follow CCW's recommendations for a 295/335 setup. I can go from there when I settle in to the car.

Incidentally, I've gotten more interested in the sale of take-offs/scrubs lately. That market is better for these sizes than my last car. Been thinking I might want to end up there. Maybe....Threads in here talk about how cheap they are. It's all relative.

A set of Toyo's has to last 12 days I bet, at $1200.

Three sets of Hoosier scrubs would be +/- $1800, delivered with two tire change/balances.

Basically scrubs increase my tire budget by 50% and every four days I'll be at the shop swapping rubber. Hmmm...

That same set of Hoosiers new costs $1600. New Hoosiers will triple my tire budget over Toyo's.

The scrub talk was interesting but doing two sets of Toyo a 24 day HPDE season for say $2500 vs six sets of scrubs for $3500 including the expense/time of five additional tire mount/balance trips makes me slow down on that idea.

I can point by a guy on Hoosiers no problem. I'm leaning towards a CCW order of C series wheels 11" and 13" and Toyo 18's, 295 and 335 next week.

Still learning from the feedback. Thanks.

96solo

Very little. I put three layers of Gorilla tape on the side of the LG coolers and sometimes it will rub it a bit. Just peel it off and no harm, no foul. Put some new tape on and there you are, no damage.

96solo

12zo... "I can point by a guy on Hoosiers no problem. I'm leaning towards a CCW order of C series wheels 11" and 13" and Toyo 18's, 295 and 335 next week."

I came to the same conclusion on the CCW's C10's at 11x18 and 13x18 rear after talking to John. With either Hoosiers or Michelins.

von zoom

Sorry joining your topic late. I have run 888s all last season on my 2010 Z06 with very good results an satisfaction. CCW wheels 18X11, 18X13 with 315 front, 335 rear. No rubbing at all. I choose 888s because I thought that I would be driving to/from the track, but I trailer the car, so I will be changing to Hoosier this year to get better grip. Don't read anything into the Hoosier statement, just want to try them out. I think that you will like the 888s, and the 315 front would be better and help eliminate under steer.

vz

12zo

Von Zoom, I would prefer the 315 front to dial out understeer. Thanks for the rub, or lack thereof, comment.

A few questions:

Do you run wheel well to rotor cooling ducts and still got no rub?

Did the computer have any issues you saw that could possibly be attributable to the bigger front tire?

Any ABS hiccups?

What mode(s) do you run the car in?

Thanks

UrbanKnight

I can answer a few of the above running hoosiers and Kuhm0 710's.

I don't have ducts...
No computer issues,
no abs issues.

I run Everything off on the track, everything on on the street...

Street tires are 295's, track are 315/345 A6, and 305/345 v710's with zero issues on any of the setups. Running ccw 2k's for track wheels, 11 and 13" widths