Silver Bullet C6

For those running the Toyo R888 305/30/19 on the stock rear wheel, how is that working out? Have you had any issues to work out once installed?
I just got my A&A S/C LS3 and am looking to the R888 in 305/30/19 as a possible tire.

thanks for you input
SC

Tzzird

Only one week in here and doing just fine. Granted, I only have about 40 miles on them. I don't particularly like the balooning look, but that's what I get for not widening the wheels. Be sure to check out Powerlab's thread on his r-compound setup. He went with a widened stock 18" (11 inches in width I believe) for the rear. The difference in price between a 19" r-compound and an 18" is almost $100 a tire. So if you plan on going through these quickly, that might be a better idea. There are some performance benefits as well.

There are a few others on here that have gone 265/35R18 and 305/30R19 on stock wheels. I'm sure they'll chime in here soon enough.

Silver Bullet C6

Thanks for the input. I'm a little concerned with the lesser overall diameter of the 295/30/19 Toyo when compared to the stock tire. The 305/30/19 comes closer in overall diameter to stock, but I was concerned with the rear wheel not being wide enough (10 inches) for the 305 width.
A forum member I wrote tells me his 295/30/19 R888s are working quite well for him.
Maybe I'm just overanalyzing.
I don't need the tires for a drag strip or racing. I just want to feel comfortable when the engine boosts up and the power reaches the wheels.

Tzzird

If I went 295 & 255 instead of what I went with, I would've saved about $70, had less balooning, but also introduce the possibility of the computers going haywire because of the diameter discrepancy. I'm not sure what the exact % cutoff is, but it's somewhere around 3-4% based off readings in the forum.

MetallicaMatt

I'm watching this thread, my stock size is 285/35/19 and I can only find Nitto Invo's in that size, and i'm throwing down 730rwhp

no racing, just want some grip on the street...

rectifyer2000

It depends on how you use the car. I put the 305/265 R888 combo on stock wheel sizes and I'm very happy. I've had zero issues: no rubbing, no fender protrusion, no other modifications necessary - just have them mounted and enjoy the G's. The difference in traction is absolutely worth every penny. I can now get traction in 1st and 2nd gear, where before it was like driving on ice. I get a little wheel hop off the line when I launch, but since you don't plan on doing a lot of racing (drags) you probably don't need to consider the 18" conversion done by Spin and Power. The tire doesn't buldge as much as I expected and the difference in diameter has no negative effects on the ride. Once again, if you were gonna race the car or launch the car at every opportunity, a wider rim/18" set-up would give improved performance. But for aggresive street use, IMO, the 305/265 on stock rims works awesome. Go for it, you won't regret it.

setxws6

I've had them on for about 9 months now with no issues. I don't daily drive my car though. I've put about 2000 miles on them in that time. They WILL hook up 600 to the wheels in mild to warm climate in 1st gear.

Tzzird

Speaking of ride... my wife noted that it's considerably smoother on the ride, especially on hard acceleration, with the R888's in. Then again, that's in comparison to my 4/32nds tread on my stock runflats.

MetallicaMatt

so nobody is worried about putting a 305/35/19 tire on instead of the 285/35/19?

5 Liter Eater

If you mean 305/30/19, No. There are two typese of people on the FI forum. Those that have already done it and love it and those of us that can't wait to get a set. I just ordered my rears. Haven't decided yet whether I will match the fronts or go with something else.

"There are 10 types of people in the world; Those that understand binary, and those that don't."

MetallicaMatt

why are you guys dropping down from a 35 to a 30?

setxws6

Because Toyo R888 only come in a 305-30-19....

BTW that's the size I've had for 9 months now. They look good IMHO.

PowerLabs

The middle number is what you divide the width by to get the sidewall height. If you make the tire wider and keep that number the same it will become too tall, and your traction control and active handling will simply not work.

MetallicaMatt

^^ Sorta what I figured, to take up some slack from the "bludge" of the wider tire, just wanted to check

maybe now I'll be able to tame some of those horses

Silver Bullet C6

Thanks for all the replies. Information and experience sharing is what makes this forum great .
Powerlabs, I read your recent post on your wheel /tire change...extremely helpful and I see 18" wheels in my future. Of course, once I'm able to put the power to the ground I'll want to take it to the track and more mods will be in order ...where does it end ?? haha

PowerLabs

No, it has nothing to do with taking up “slack” or bulge; you want the rear tire to be within +- 3% of the factory size (even when all the thread has been worn down; this means the actual size difference allowable can be even smaller). A 305 35 18 is simply too tall whereas a 305 30 18 is within less than 1% of the factory size. Whether it bulges or not depends on how wide of a rim it is mounted on, is completely irrelevant to the traction control and active handling systems which work by monitoring the relative speeds of all 4 tires and as such get confused when they see a tire rotating at non factory rates.

MetallicaMatt

i'll be running on the stock rims, i did some more searching, do I need to bump up the front tires to not throw any codes or anything if I went with 305/30/19?

rectifyer2000

Now I'm confused by this statement. How does mounting a lower profile tire (30 series vs. 35 series) on a wheel that's already an inch shorter that stock (18" rears) bring that combination closer to stock tolerances?

HuskerBullet

I haven't done it yet, but I'm saving my money for it where I've read of at least a couple of people here on the forum have used the Toyo R888 295/30-18 on the front with a 10.5" wheel (don't know what offset, if any) and the 335/30-18 on the rear with a 12.5" wheel (of course, with the Z06 wide body fenders). You gotta admit that probably not only looks very intimidating, but will definately plant your machine to the road....

PowerLabs

My answer referred to his question about mounting them on 19" rims.
On MY particular setup, with the 18" rims on the back, I run 305/35R18.

This is really very simple, but if anyone is struggling with the concept, just go to the Tire Size Calculator, input your factory tire size, and then input all the other sizes you are considering: If the size variation is more than 3%, you can count on your active handling and traction control not working. If the size variation is *almost* 3%, you can count on A/C and T/C not working after the tire wears down some. You want the overall diameter of the tire to be as close to stock as possible, and it does not matter if you have a 285/35R19, a 325/30R19, a 315/35R18, a 285/30R20, etc...
The car doesn't care how wide the tire it, is doesn't care how big the wheels are, all that matters is that the overall diameter remains within factory specs.