I run RC-1s. Can't kill em.
I run RC-1s. Can't kill em.
wake74 said:It appears the RS4s are out of stock in the 245/17 size, at least at Tire Rack and the other places that popped up in a quick search. I normally just order from TR so I don't have much experience with the other online retailers.
Any thoughts on other stores that I should check with for availability?
245 on a 7.5 inch wheel is not ideal. They have 225s that will be much better on that size wheel.
The contact patch size will be roughly the same. You MAY give up some cornering grip with the narrower tire but the response of the car will be sharper and more communicative. It will be easier to drive and for that reason, I would bet that the laptimes are actually faster with the narrower tire.
225s
235s
245s are NOT recommended for anything less than an 8" wide wheel.
I have run the Federal RSRR 235/40/17 on an 8.5" wheel on your chassis, your suspension. If you run with NCC, you have seen me do it. If Tarheel, probably not.
Speaking for myself, if I had been using those tires as I transitioned to B . . . it might have slowed down my learning some. Couple other reasons not to do it. (1) They have a lot of tread on them, but it wears down fairly soon to the point that I won't drive home from the track in the rain; it's just too sketch. (2) Can't use them or even leave them outside in the winter. But you have a trailer, so maybe you're willing to put up with swapping and storing. I get mine from Hotstickytires on Ebay, or through Amazon, depending on what's cheapest at the time.
I'm going to suggest P Zero Nero GT in 215/40/17 or 225/45/17. I would use the 225's on 7.5" wheels because I'm comfortable running an E36 on 45 aspect tires anyway, and the 215 is really a little too narrow. They cost about $125 a corner. I tried them out last year as an "arrive and drive" tire for my E92 M3. This year, I'm using slicks on the E36, so I have ordered a set of the P Zeros to be my transit, parked-in-the-driveway, and rain tires.
When you wear those out, I would give serious consideration to Nitto NT-01 in 225/45/17. Not good for wet highway use or winter-hardy, but they stick very nicely and don't heat cycle out, all the way to the cords.
Thanks for the additional comments.
I'm not planning to run 245 width on my existing spare set of 7.5" of rims. I would need to pick up a set of 8.5" ones for that, which I'm looking for locally. I thought I had a line on proper 17x9 race rims and used 255 RSRs but that doesn't seem to be panning out with the seller.
I will always bring a trailer with me anyway, for tools, canopy, chairs, etc. It's no issue to drive on the cheapo street tires that came with the car and swap at the track. That's what electric impacts are for :-)
Wanted to provide an update. I was able to buy 6 ea. 17x8.5 Kosei rims locally here in Raleigh. With 8.5" rims in hand, I purchased a set of RS4s in 235/45/17. The 245s were still out of stock everywhere. They were very tight in the rear using Bilstein Sports and H&R Springs. Of course, I didn't actually test fit them until Friday night at the track :-)
Nothing three guys couldn't fix first thing Saturday morning. Jack handle from one guys truck, and one guy pushing the car forward, one backward, one manning the jack handle, we redneck rolled the fenders in no time. Someone else in the track loaned a proper fender roller to us later in the day so I cleaned up the rolling job a bit on Saturday night. The fender roller makes the job MUCH easier.
The RS4s were great. I would say as sticky as the old RA1s, but were more consistent audibly which was nice. Oh, and VIR Grand is an absolute blast of a track!
Interesting. What's the offset on the Koseis? I have used Koseis 17 x 8.5 ET40 and the Federal 235/40 on the E36 without clearance issues, other than a little bit of edge rubbing on the front fender wells at full lock. They are a couple tenths wider at the tread and section than the RS4s. But the diameter of the RS4s is 25.1 vs 24.3 for the Federals. Seems like that's enough to make the difference between rolling the fenders, and not rolling the fenders. Unless your offset is lower than 40.
In reply to JBasham :
They are either 40 or 41, I'd have to look. I hit the brake cooling ducts long before full lock at the front, so I'm not sure if they would rub in the front or not. It wasn't a hard rub in the rear, but I could see white paint on the tire just driving around hte paddock. Too close for my comfort, and lots of room now with the fender roll.
It's important to look at the actual specs on tires, too. Some manufacturers' 235s can be wider than others' 245s, etc.
Well, your issue wasn't the width of the tire, but the sidewall. Proper size with a 45 series tire is a 225, not a 235. Obviously if you could've gotten 245-40's that would've been the preferred size.
I also feel that the latest street auto-x tires are just as sticky as NT01's, RA1's etc. The latter handle heat better, for longer but don't give any more grip compared to the former.
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