Fredforce

Toddiesel

Here's a comparison of the two tire sizes, for everyone's reference

RoxyCarter

Has anyone done any road course racing with high lateral G on these tires? How do they compare to the super sports or the cup 2s? The taller sidewalls on the rear wheels will be better for straight line grip, but I wanted to see how bad the negative effects may be on hard cornering.

I assume they are middle of the road between the 2, closer to the cups in racing rubber compound, but want to hear anyone with experience.

thanks

Toddiesel

I haven't tested them, but they are definitely NOT in the middle between PSS and SC2s. They are far stickier than either. The SC2s are a streetable competition tire where as the R888Rs are considered racetrack and autocross only, and of course the PSS is just max performance summer tire.

baystealth2430

So I guess my question is. Is the .4 inches of width that I will be losing going to be made up for in better grip? Is this grip going to be comparable to my drag radial setup Nitto 05R

Checkmate1

Jeez - +4% diameter can throw off the speedo. Can also cause traction control to cut power abruptly.

No go for me on the 325/25/20's. I've seen far to many C7's with taller tires get sloppy because traction control kicks in.

Toddiesel

For a second I thought you wrote 4 inches, not 0.4 and I was going to have to give you a math lesson in converting mm to inches Anyway from everything I've read/heard from many sources is that it hands down is going to provide far better grip than either stock Michelins, especially for launching. All I've seen is people saying how well they hook off the line. There does seem to be a little debate about lateral movement, but most seem to be ruling in favor of the Toyos, but I haven't seen a single person that said either of the Michelins were better or even close to the R888R off the line.

Toddiesel

Maybe the C7s are more finicky than other cars, but before this, I had a 2013 mustang gt and I went up about an inch and a half in tire height and it threw off my speedo really bad, but I never once had an issue with traction control acting weird. I don't see why it would.

baystealth2430

So here is what I am thinking about going with Toyo R888R 285/35/19 on front and Toyo R888R 325/30/20 on the rear. That a little bit taller on both front and back (less than an inch) and 0.4 inches narrower on the rear. Any idea how much this is going to throw off the speedo? Also is the speedo difference able to be fixed by my tuner. Also anyone got any insight into the traction control issue noted earlier? Never heard of this just because of taller tires.

Toddiesel

If you scroll not even halfway up the page, I shared a pic of how it compares to the factory tire including speedo change. The fronts won't affect the speedo. Yes, a speedo change can be corrected by a tune.

baystealth2430

I saw that chart you posted but I also know different manufactures measure the width from a different spot. Not all 335 widths are the same. I found this out while shopping for my drag radials. I was hoping for some real world comparisons not just some chart that is generic. My nitto drag radials are 345 wide and I noticed very little if any difference from the 335 stock ones. I am just hoping the 325 wide are the same way.

Toddiesel

Well if they were 325/25, you probably wouldn't notice a difference. 25% of 10mm doesn't increase the height a whole hell of a lot (0.1 inches, thereabouts). It's that extra 5% height that messes you up. Even if the 325 and 335 are the exact same width, the 325/30 would still be about 0.7 inches taller per side, so 1.4 inches overall (going off 5% of a 335 width. going off a 325, it's more like 1.3). The math is there, but I understand what you're saying about the manufacturers not measuring tires the same (which i never understood. do they have different rulers?? a millimeter is a dang millimeter!), but that's going to give you a PRETTY close approximation, give or take like 2%

HessViper

speedo change is on the chart above a few posts

Z06Brucey

Have you pulled the trigger on these tires yet?

Toddiesel

My Z is in the shop right now and I plan on putting the 325/30/20s on the rear. I will definitely let everyone know how they work out once I get some miles on them. It will be a few weeks still before it comes out of the shop though.

baystealth2430

Hope to have them on there this week. Going to a private track rental on Wednesday but I will be running my nitto drag radials on the rear. My tire shop was having a a hard time finding the fronts. They can get the rears in a day or two.

baystealth2430

Just ordered them from Tire Rack. Order says be here Tuesday. So I can get mounted on Tuesday or Wednesday morning. Will keep yall updated with pictures once I get them all mounted and on my car

jbsblownc5

I currently run Toyo R888Rs on my sig wheels, 275/35/18s on the front and 345/30/192 on the rear, GREAT TIRE!

I may put the R888rs on the stock wheels as well...

The Toyo R888rs are a little wider then the Toyo R888s were, so in my opinion, a 325 Toyo R888R will be VERY close to a stock 335 tire, and out grip it in almost every scenario...

Z06Brucey

Awesome man! I can't wait to hear the results!

Oh4GTO

Same here. Eager too see how tall they are.