180mph tires ?

Eljaro · #1 (**permalink**) 06-05-2005, 09:38 AM

I took out my Contemporary today to check the new jetting of my carb and got carried away on the Autopista doing 150mph at 5500rpm. The engine was still pulling for more but I backed off because my Yokohamas are rated T only good for about 118mph.
I am thinking to get a set of 17inch wheels and tires. Who makes a good 17" Halibrand look wheel? I have calculated that I would need 335-35/17 and 255-45/17 to get the correct tire height.
I would like to know what you are wearing on your 17 inch wheels and you comment on the feel of 17 inch compared to 15 wheel.

tryce · #2 (**permalink**) 06-05-2005, 01:00 PM

Just went through the ordeal myself. I had nitto 555 drags on the car Treadwear 100, Traction A, Temperature A. 315-35/17s Rear. I had 3000 miles on them. Went to Willow Springs Race Way raod course a month a go and the right rear side wall went on my third lap in turn one. Caused fender damage but could have been much worse. Kept udder control and parked it in the dirt. Side wall of the tire was way to soft for road course. My BAD. I Would not TRUST them even for a local mountain road fun run on a saturday after that expierence.

Not a very good selection of manufactures to choose from in this size.

I chose to upgrade and go with BF Goodrich G-Force TA KDs. Make sure you look at the KDs. They are a Special tire and somewhat hard to find. They come in a right and a left. Locally in LA there was one left hand tire the other one was shipped from TX for the right side. Treadwear 200, Traction AA, Temperature A. I have 200 miles on them and they hook up great. Look in my gallary for these new ones.

Eljaro · #3 (**permalink**) 06-08-2005, 05:07 PM

tryce
In the size I mentioned in my first post I have found Michelin Pilot and Pirelli P-Zero, both have matching 335/35-17 and 255/45-17 tires. Should be good for alot of speed.
Drag tires are no good on road course because of soft sidewalls. You experience confirms this. Lucky you it only ripped your fender. Easy fix, not so the paint.
BTW, is there some way to contact PS Engineeering other than by phone. Do they have a fax or an E-mail ?
eljaro

427sharpe · #4 (**permalink**) 06-08-2005, 07:36 PM

Beware of using treadwear, traction and temp ratings on tires...they are a guidline against a particular mfgs 'base' drum tire, and each mfg has their own standard so it is useless to compare a Goodyear treadwear rating against a Bridgestone.
For best comparison, use the performance index (sometimes called a speed rating) because it is a standard applied across brands. S rating means good for sustained speeds of 112, T 118, H 130. V 149, W160 and Y 149+. So for a 180MPH tire, you must find one with a Y service rating to be sure. Generally an H rated tire will last longer than a V rated, but not grip as well. As for wet weather traction, it's trial and error. I personally think the Firestone Firehawk SZ50 EP is the best rain tire I have ever seen (seems like most Corvette owners clubs agree!). I have a set on my Lincoln and my Cobra, and they grip better and last a lot longer than the Eagle F1's I had before.

SCOBRAC · #5 (**permalink**) 06-08-2005, 08:20 PM

PS Engineering... Photos in my gallery with 17 x 9.5" and 17x11" on back. That will allow you to run 275/ 40 on front and use either 315/35 for low profile look (my rear end is quite low) or 335/35 if you are happy with a little higher stance in the rear. The 255's are a poor choice for the front as they are too narrow and quite a bit smaller diameter than the rear. 255/40 and 315/35 are both 26.2" across and maintain a standard cobra tire outside diameter.

I run the Eagle F-1 supercar tire www.tirerack.com they are Y rated to 186 mph. I'm running 3.54:1 with a 4 speed and prefer not wringing it out to much past 6,000 but the Contemporary is rock solid at 155-160 with these tires on it.

You have to call Phil at PSE at 9 am PDT (GMT-7) leave him a message tell him where you are. Tell him you will call him back in one hour (he is quite busy in his shop and cannot get to the phone easily)...

Regards,

Eljaro · #6 (**permalink**) 06-09-2005, 02:27 AM

michael,
you say:

Quote:

255/40 and 315/35 are both 26.2" across and maintain a standard cobra tire outside diameter.

you mean 275/40 in front ?

I suppose you have the coilover front suspension in your Contemporary. Which offset did you order your 17" wheels with ? Did you have to modify anything in order to fit the 9,5" front wheel without hitting steering arms or suspension parts ?
Thanks
Stefan

SCOBRAC · #7 (**permalink**) 08-14-2005, 11:19 PM

Careful... You know Englands speed limits were inspired by such spirited Cobra play.

Of course 275 40 in front 315 35 in back, the 255 was a typo. I have the standard torsion bar suspension. The backspacing on the front are 5 1/2" the wheels are 9 1/2" no modification was required. The backspacing in the rear is 6 1/2" they are 11" wide over all.

Phil Schmidt will craft you the very best wheels for whatever combination you have. I have noticed he seems a little backed up lately. It's worth the wait.

Don · #8 (**permalink**) 08-15-2005, 07:59 AM

For comparison purposes, from the 2006 Corvette Z06 specs:

" deliver a top speed of more than 190 mph on a race track. "

"18 x 9.5-inch front wheels with 275/35ZR18 tires and 19 x 12-inch rear wheels with 325/30ZR19 tires"

Specs did not mention the Brand

The 2002 Z06 with an advertised top speed of 171 MPH, does not mention sustained:

Goodyear Eagle F1:

Front: P265/40ZR17
Rear: P295/35ZR18

cob53 · #9 (**permalink**) 08-15-2005, 10:57 AM

Hola Eljaro

No speedlimit in Mallorca?

Rico

scootter · #10 (**permalink**) 08-15-2005, 12:11 PM

I am running the Goodyear F1 Super car tires that are 315/45 ZR17 on the rear and 275/40 ZR17 on the front. The 315/45 are perfect because they are not such a low profile and they hook up great. The only problem is that they do not make the 315/45's anymore. So I am looking at having to go lower profile and wider.
I have some pics too.
Scott