weekendracer

I picked up my c5z this spring and have just been burning off the RE760's that came with it, as I believe it is easier to learn the limits of a car on less than ideal rubber. Next season I want to stop up to competitive rubber.

I see that most people bump up the front wheel to the 18x9.5 to get better rubber choices. I am leaning towards this option but I am also looking at keeping the 17/18 setup.

The biggest problem as everyone knows is finding tires in these sizes. The rear is a pretty easy choice I would say with the 295/35 Rival. You can also get a nt05 in the 295 however from what I hear there is not much comparison.

Now my question is for fronts. You can have your choice of fronts in 255/40 with RS3/ rivals, Zii's (Although I think these are being discontinued.) Or you can get the nt05 in a 275.

Would the size difference of the nt05 possibly make it a better choice over a smaller Stickier tire?

Right now I am thinking 255 rs3 for their great lateral grip, with 295 rivals out back

Or 275 nt05's up from with 295 rivals in the rear

Or 275/295 NT05's

Thoughts?

JRL

This , from the B street build thread, posted by Ryan Otis on A street tires:

I think Glen Hernandez and I are both in agreement that the RS3v2 is the best tire option for the c5z right now. If I hadn't rolled backwards out of the staging lights for my best right side run at the Packwood Pro we would have been about a tenth apart. He took #2 overall PAX behind Godzilla, so the car is plenty competitive according to the calculators.

We are both running 265/285 on 18's. My tires have exactly 160 runs on them right now (after the Pro), they were flipped after the Crows Landing events. Glen's set was brand new and used for one local event before the Packwood tour so he is likely in the 30-run range. Based on the times I'd say my well-worn tires are still very competitive. My 60' times and RTs were pretty crappy until the super challenge, but that wasn't the fault of the tire. I made it to the final four where I lost by .6sec to someone who broke out by .6sec so I was running right on top of the dial-in set by Glen.

The tires have certainly fulfilled my expectations with regards to competitive life, if they stay fast over the next couple of local events I'll probably run them on Saturday morning at the Pro Finale in Lincoln.

I should probably add that Glen dumped his AD08Rs in favor of the RS3v2.

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Last edited by rotis; 07-15-2014 at 03:44 PM. Reason: Glen ditched Yoks, not Rivals.

Matt_27

Avoid the NT05. They are no where near a top street tire like the RS3V2, ZII, or Rival. The other advantage of 18s up front is you get a smaller and therefore stiffer sidewall for better response.

brenb

www.hoosiertire.com

hklvette

I second avoiding the NT05 for serious auto-x use. They're only advantage is that they're cheap. They work well as a street tire, but even then I'd use the 555 because its the same compound, just thicker.

Zachreligious

Not sure if joking. A Street is 140 treadwear this year - 200 in 2015.

rotis

With stock wheels I'd run 255/40-17 and 285/35-18 RS3v2. My best 60' at the Packwood Pro was 2.0 on the RS3v2, that's about as good as it gets on street tires so power delivery isn't a problem with this tire.

I personally think the 18" front is worth it for the shorter sidewall, but I haven't tested it against a stock 17/18 setup to see if there is any meaningful difference.

dhowdy

What rims are you guys running? Putting some rear wagon wheels up front seems like a cheap solution that would only cost you a couple pounds.

talon95

Maybe you can find some if you shop around, but TR has been out of the 285's for a while now.

Solofast

I mounted up a set of the 255/17 fronts and 285/18 rears (from the Tire Rack the first week in July) on my 04 Z and the grip is very good. At the limit it seems like the car is a bit loose, but I haven't had it on a course yet. Perhaps a bit more front bar would take care of it, but the limits are pretty high and the response is good. Most sticky "street" tire I've seen in years.... I'll get it out in a couple of weeks and see for sure. I also have a set of poly bushings for the front stock bar and that may be enough to balance it out.

talon95

I did notice the Rivals are back in stock for anyone that's interested, even the 335 finally.

TypeIsCheap

Nice job out to all the AS trophy winners at Nationals! Especially Rotis, so close!

Based on those results it looks like I'm getting some RS3v2's for the c5z next year. Any thoughts on the 305-19 for the rear? Extra width not needed?

I was working course during AS, cars looked great but man night and day between the light and tight underpowered CSP cars and big powerful soft beasts in AS (except for the CR). I flew in and ran FP99 with my buddy this year (my "off" year).

weekendracer

Thanks for posting about the results and its good to hear the RS3v2 is the tire to have unless someone comes out with something new by next year.

The problems I have found with the 19" rim is you just can't find a inexpensive 19x10.5 Rim everything is 19x10 or 11. you will end up paying close to around $3k just to move up to a legal 19x10.5 rear rim. If guys were seeming to run well on the 285 I will stick with that, but if you have the money to burn the extra 20mm won't hurt one bit.

rotis

Thanks, I really needed a third run on the East course if I wanted to catch Daddio. Everyone already knows he is a fantastic driver, he was so fast out of the box it was crazy. I was too slow to get comfortable with the feel of the car on the surface and really needed three runs to find the speed. He was crazy fast from the first run, certainly a learning experience for me and something for me to work on next year.

A cheap rear wheel option for 19x10.5 is the TSW Panorama. Glen ran those on the rear with his AD08Rs earlier in the year (I think maybe with a spacer? not sure). Using base C5 thin-spoke rears in the front. They are actually a pretty decent match in terms of spoke design and don't look too out of place if they are all matte/flat black. I have a set of thin-spokes for the front, and also a pair of magnesium rears for the front.

I needed more tire for sure. Based on Lane Borg being successful with the 285's on his 18x9.5 rears I'm pretty sure the optimal setup for a C5Z is something like 275-285f/305r with 18/19 on the RS3v2.

I'm not going to be making any drastic changes until early next year when I see what sizes are going to be offered with the new crop of street tires. I'm expecting both Bridgestone and BFG to have something of interest.

(edit: I posted links to videos, but couldn't figure out how to make them not-embedded in the post... which is super annoying, so I removed them)

ltborg

+1. Daddio had that setup on his C6Z and the tires looked fairly stretched. I bet they would fit nice and square on C5Z rim widths. It would just be a matter of finding the wheels.

hklvette

Even the fronts? The front C6Z wheels are the same diameter and width as base C5 rears (IIRC). The only difference is that they have less offset to clear the bigger calipers.

The rears are completely different, as talon outlines below.

talon95

C6Z wheel sizes are,

18x9.5
19x12

Offsets are different then the C5Z, even on the front.

SteveC68

What was Daddio driving? The results say "2007 Chevrolet Corvette Z". I'm guessing that is a Z51? The Solo rules are sort of confusing on where the C6 Z06 goes.

dhowdy

Says Z06

Super Street class (SS)
Chevrolet

• Corvette Stingray (C7) (2014)
• Corvette ZR1 (2009-13)

A Street class (AS)
Chevrolet

• Corvette (C6, non-ZR1) (2005-13)
• Corvette Z06 (C5) (2001-04)

talon95

Yea it's a C6Z.