Chumpaumpalumpa

Hello everyone! I have just had new toyo R888 installed on my 2008 Vette. It was time to buy tires and i had some old Firestone fire hawk wide ovals on there previously and was looking for a much grippier tire to run with stock suspension. The R888 understeer and move around waaay more than the bald firehawks on their before and they dont grip any better in the curves. The Toyos are also 10mm wider front and rear than the previous fire hawks. This doesnt make sense and is really frustrating. I'm running around not knowing what to do! please let me know what options i have to improve grip without changing suspension components if possible. Thanks. Also this is a street car driven on the street 99.99% of the time and it rarely sees the track but is not daily driven.

timd38

I bought Michelin Super Sports and am very happy with them. Good grip and comfort.

smellya

what tire pressures are you running? I run 26 front and rear cold. Hot they are 34-36... The are pretty sticky at the track. They are not a hoosier but I have to drive to the track for now.

Chumpaumpalumpa

Ive heard about the groove of death so im running 30 cold n hot on the street they see about 36. but they slide and move around so much theyre quite unpredictable in the corners. any ideas as to why they are so slippery its becoming a major problem. also people keep saying they grip better at higher pressures but bleow 40psi.

theVcar

I don't get this. Way too under steer? How do you drive? You don't drive road course so how are you testing them. Any on/off ramp can be an easy test. If my impala can do it at 30 my vette can do it at 55 mph. That's not good enough?

SUB VETTE

Experiment with different tire pressures until you find what works best for you. Don't forget that you need to get a few miles on those new tires before their true characteristics will become evident and they settle in. I'm running Michelin PS2ZP's and they are great. Much better than the two previous sets of GY Supercars.

Chumpaumpalumpa

it never understeered at all on the old tires which is weird and im mostly canyon carving. but grip levels are the same or even a little lower on the new toyos. its just the cornering im most concerned about because they grip fine in a straight line but very slippery mid-corner.

Chumpaumpalumpa

Ill take that into consideration next time i buy.

smellya

I got them nice and hot the first time out with them and let them sit for around 48 hrs before I went to the track. The high tire pressures are for the cars with the skinny tires. How wide of a tire are you running? I am running 295/30/18 fronts and 335/30/18 rears. I have not had any grip issues going into or mid turn.

Chumpaumpalumpa

255/35/18 front
295/30/19 rears

whats weird is they're less grippy than the 245 front and 285 rears i had on before......its on a stock rim which i was told they would fit on and it seems they do.

TorontoC6

What is the ambient air temperature? Did you put some heat into the tires? The R888 is a R-compound track tire which will have less grip than regular street tires when cold. They also like more camber than a regular street tire. If your hot tire pressure is not at least 5 degrees higher than your cold pressure, then you have not got the tire up to temp and won't getting good grip.

moose.b3

R888's need heat

Chumpaumpalumpa

Ambient air temp has been around 70-85 degrees since I've gotten them and yes they were definitely more than 5 degrees hotter than cold temp and the pressure was up 5 degrees all around also. That's what's weird is everything now seems to be optimum other than suspension, yet some how wider track tires with heat in them = same grip as some old bald friehawks??

MARSC6

They will come around after you break them in.

Chumpaumpalumpa

how many miles u think will that take?......ive had them heat cycled by tirerack as well.
also how long can they sit before they flat spot.

96GS#007

: As pointed out by another poster, you bought a TRACK TIRE. They need heat to work like you typically get after a couple 7/10s laps on a road course. You will not get them hot enough on the street.

Time to sell or save them for track days.

Chumpaumpalumpa

how hot do they need to get? 290F 310 degrees?
i drive them pretty hard in the canyons thats still not enough to get them hot enough, even on hot days?

thanks for the info guys as this is a learning experience for me

96GS#007

Typically 190* - 200* as measured with a probe...ie not the surface temp of the tire.

Canyon roads simply do not compare to a real race track. In all my years of instructing for various clubs...BMW, Porsche, Audi, the NCM, etc...this has been confirmed over and over again by participants. Individual turns may be as challenging or exhilarating on a canyon run, but there's just not the overall level of required performance. Another way to look at it....30 minutes on a relatively technical track would equal a canyon run that's in the neighborhood of 20 miles with 250-300 turns and speeds on the straights exceeding 130mph and in the case of modified cars or Z06s, nearing the mid 140s.

SUB VETTE

Go on to Tirerack.com and look up your tire. You will see it is a racetrack or autocross only tire with operating temperatures recommended to be 160 - 220. Not a street tire at all. You just bought the wrong tire.

MARSC6

I've let them sit for over a month and never had any issues with flat spots.

I've been using R888s as my primary rear tire for about 4 years now. When new it did take a few times out for them to break in and start gripping well. Don't give up on them yet.