Scotthmt

55 deg ground temp 640rwhp 345 19” r888r’s that are newish, traction in 2nd gear is currently non existent. Paying attention to these nitto555r2 threads, might be the next move if the 888r don’t heavily improve with warmer temps.

grinder11

Problem for me is I have my LS7 power in a C5. That said, I want to keep my 18" rear wheels. I'd give the MT ETStreet SS tires a shot, but they're limited in choices for 18" wheels. I don't typically drive at 150+mph, so the high speed stability doesn't concern me so much. I want to stay around a 315/30/18, or no taller than a 305/35/18. Other truly sticky tires have virtually no tread. Wish the Nitto 555R2s came in a bit softer rubber with same tread pattern. I see a 100 treadwear rating, but I wish they had an optional 40 treadwear version. Waaaaahh!!!

Stroker87

Im going to see how these NT555RII's do bolted on to my c5 zo6 it's got a 415 stroker that's putting down 514/520 to the wheels probably around 50 hp/tq then the zr1 makes at the wheels, I got one easy pass in at the track it ran 11.02 @ 126mph I'm sure if I ran it harder would clip high 10's

HowWhyWhyHow

They get really really hard and slick under 60*. I burnout will get you a couple pulls if the road surface is cool, but you'll probably have to do another burnout to keep doing pulls.

Once it hits 70 outside and the sun hits the road they Improve drastically. Above 80 and they hook all day. Great tire when it's warm

HowWhyWhyHow

Toyo RR tread wear 40 comes in those sizes. Absolutely not okay to drive in the rain though. Those are my next tires.

GhostBluZ06

what kind of front tires were you running?

Stroker87

I think it was 18" continental stock GS tires i ran GS rims for a shot time

ElisTwoCents

That's pretty accurate in my experience. I used to roll with the 555Rs (both old and newer versions) for a long time, then eventually moved to R888R designs. I did find that the OLD design of the Nitto 555r seemed to walk just a smidge after 140mph, I've never had that experience with the Toyos up to 167mph. Maybe the new 555rII design holds better structurally at higher speeds.

A thing to note: Toyo Tire Holdings owns both Nitto/Toyo, the compound for both tires carries a treadwear rating of 100 AA A, I'm almost sure the compound is the same mixture with the difference coming in the carcass of the tire itself. I wouldn't be shocked if they were both manufactured same White, Georgia factory

GhostBluZ06

if they were runflats thats why it got sketchy at higher speeds...

EvanZR1

Stock C6 GS tires were Goodyear F1 G2 run-flats.

No, run-flats don't get sketchy at high speed. The Goodyear F1s are speed-rated (Y) for over 186MPH. I've had multiple sets/brands of run-flat/ZP tires to well over 150MPH, and they were all rock solid. Stroker87's issue was from the M/T Street SS, it's a very well known and documented issue that many people (including myself) have experienced (and not just on Corvettes).

Stroker87

not run flats continental tires up front

GhostBluZ06

Runflats mixed with a drag radial in the rear made my C7 and many others sketchy at higher speeds.

Stroker87

As EvanZR1 said all over the place online guys complaining about the sway and how sketchy those tires are on every type of car camaro's, mustang's, hellkat's and so on

grinder11

It's my understanding you don't mix runflats on one end, and conventional radials on the other. Kinda like not mixing radials with bias plys.

GhostBluZ06

Right^^^ this! Forgot about the bias plys and I also forgot the easy well to tell the bias plys from the reg radials

grinder11

So you're saying you ran the 11.02 with the Nittos? It's been a couple weeks since you posted this, so I'm wondering if you've tried another couple of runs in the slightly warmer weather? I'm a bit anxious, can you tell, lol?!!

Dmorgan01

Both these videos were on my 345-19 R2’s on my stock wheels. Work great for me. 1.559 short time in the track video. 628whp std.

grinder11

Best I could do for the 555r2s in 18" wheels would be a 305/35/18. I have enough wheels for 315/30/18s, but Nitto doesn't offer the 555r2 in that size. Toyo TQs are available in the 315/30/18 size, but I'm thinking the 35 sidewall will help on launch, and may be just a bit easier on the drivetrain. Anyone tried the TQ series Toyo Proxes?

Stroker87

no at the track i run slicks, I have not tried the Nitto on the track but hopefully soon ill have the chance

grinder11

What 1/4 mile results did you get from that 1.56 60'? Thanks..