Vinca1

I'm looking for some tires to use on the track and for driving around town for my C5 Z06. For the fronts, I can only get 275s. For the rears I can get 315s which is the same size I run my Hoosier A6s. I run 295s in the front with the Hoosiers. Will 275s be too narrow and have any adverse handling effects?

Sidney004

The adverse handling effect might be switching from Hoosier A6's to Toyo R888's.

Vinca1

True, but I don't want to run my Hoosiers around town.

EvilBoffin

HA - No doubt!!

To the OP's question though - how wide are the wheels you intend to mount these tires onto?

I've got 275's RA1's on 18x10 CCW's and 305's out back on 18x11's. The combo seemed to feel nicely balanced and work well on-track at VIR and on the street, though there is plenty of room for wider rubber on these particular wheels.

I also have 285/18 & 315/19 Hoosier A6's mounted on OEM C6 wheels. The skinny wheels (required for my autocross class) cause these tires to lose enough width so that they end up being the exact SAME widths as the 275/305 Toyos.

My only concern for you is - do you run into any heavy rain conditions on the street or track? I elected to get RA1's instead of R888's, because they are considered (even by Toyo's own rating system) to be a little better in the rain.

Vinca1

I have an extra set of stock C5 Z06 wheels that I will use for the Toyos. I can't remember what they are in width, but the A6s at 295/315 seem to fit on them ok.

As far as the rain is concerned, it is not a factor as far as I am concerned at this point in time. Basically, when it rains, I lose all interest in driving.

The Toyos are available for the rear in a 305 width, do you think that is a better choice in this case than the 315s?

sperkins

I would highly recommend the NItto 555RII Extreme Road Race tires. I ran a 275/305 combo on my '03 Z for nearly an entire season at many tracks across the southeast with good results. You need to remember though that the grip falls off any DOT tire the more you drive them on the street (even if the tread still looks good). I figure I had nearly 200 heat cycles in mine before they were completely worn out and I could definately tell at the track that the tire lost grip as they got older. But....they stick like crazy when they're fresh.

http://www.nittotire.com/#index%2Etire%2Ent555r2



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Sidney004

The 305 R888 is a 305/35/18 with a dia of 26.3" and a weight of 33#; the 315 is a 315/30/18 with a dia of 25.5" and a weight of(still heavy) 30#. The 305 will increase your C.G., increase your unsprung weight(much further compared to the A6, does anyone have the weight of the A6?) and lengthen your gearing. My vote for the lesser of two evils is the 315/30/18.

GettReal

I 100% agree however good luck finding Nittos these days.. ugh

I am just about done with my Nittos and have to go to Hoosiers now since I cant find any Nittos

gkmccready

I run my C6 with CCWs in 18x11 F/R with 295/30r18 fronts, and 305/35r18 rears. Car feels okay this way. I always want more tire/traction, though. :-) You have to run a fair amount (-2deg) up front to have the 295 clear the fender lip. I'm strongly considering an 18x10 275mm set up for the street. The rears could fit an 18x11.5 or maybe even an 18x12 with little effort.

EvilBoffin

I agree with Sidney about the 315's. If the 315 had been available in an RA1, I would have bought that instead of the 305's. Seems like we can always take advantage of additional rear tire grip with these cars. I've got 3/32nd's rear toe-in to put the power down well, and still feel that more rear tire would be a good thing.

As for rain, I understand your situation. In my case, torrential downpours on the way to a track or - worse - while I am ON track can happen unpredictably here on the East coast. And I can't carry an extra set of tires with me quite yet.

Just after registering for the NCM event at VIR and heading to the track, I got caught in a SEVERE rain storm. Even with pretty good tread left on the RA1's, it was a white-knuckle ride at only 30 MPH. The 888's would have very loudly told me to "STOP, DUMBASS"

avizandum

How would these run on a cool spring day here in MI for AutoX with no opportunity to warm up? I've been considering these for a while.

I've been thinking 265/35/18 & 305/30/19 as these are closest to stock diameters & rake.

tmak26b

After a few track days on the treaded R888, I am skeptical about them being faster than shaved RA1. I dont know who is the SOB out there that initially said they are faster than shaved RA1s, but he should get a beating of some sort as they are absolutely not. According to my datalog, my old car, which doesnt handle as good, was pulling more Gs in a lot of turns. I honestly don't know if it will get better when all the treads are gone, but it is currently scary right now.

I use them for autocrosses, they are not bad, but dont expect winning anything other than local events.

EvilBoffin

John Purner of CCW is definitely NOT a fan of the R888, and I took his recommendation to get the RA1's instead. He said that the World Challenge teams that he sells Toyos & wheels to are struggling to get better lap times on the 888's.

That's not to say I still wouldn't like to sample a set of 888's myself some day, cause they offer them in some nice 18" sizes...

gkmccready

I got the R888s back when John liked them. They also offered a better front size for the 18x11 front wheel we decided to run. I'll have to call him to see what he's happy with these days.

tmak26b

I remember reading someone's review on some site about how his unshaved R888 is 1.5 sec faster than the RA1s (Before it came out). I actually believed it at first as I figure you have to have some skills or pulls in order to be one of the first person to drive a brand new tire. Apparently the guy either can't drive or is paid by Toyo to lie. I spent all Friday blaming myself for going too slow, but upon seeing my data from the datalog. I can see why I was 1-2 sec off my normal pace.

I still like the tire, but I am just pissed that it is slower than the RA1. Will the tire be faster when they have no tread left? I dont know. I have 4500 street/track/autox miles on it, I still have about 2/32nds left. I will see what I can find out.