[thumpetto007]

I have a 1995 L bodied 2001 2.5rs (2700lbs with driver) with a NA high compression build (190 WTQ) coilovers, bars, braces, mounts... I'd like to keep most of my handling/steering characteristics, and drivetrain mass low, while maximizing grip at the track. Also, tire cost is also a factor, and usually the smaller the tire, the cheaper it is, so more money for track days, brake pads, fluids...

I've seen varied answers to my question of "what size rims should I get?"

Some people swear by 17 inch rims at the track, others have told me to get 16 or even 15 inch diameter rims. (For drivetrain mass reduction and more tire sidewall)

I'm thinking 245 width tires are a good balance between grip, transient response, weight and other characteristics. So an 8 inch rim width would be necessary.

Any input is appreciated, thanks!

 

[X379]

Well lets see, I've driven with 16's, 17's, 18's....

16's were nice, I mostly drove the stockers with 205/55s, even with a good alignment for aggressive driving, the tires were deflecting quite a bit and didn't offer enough grip under high speed corners.

17's, I had both 225/45s, as well as 245/45s. The 225s weren't bad at all, I think if the tires were better I'd have enjoyed them more, but they do let go fairly linearly when I used them. The 245s were just awesome though. I have hankook rs2's on there, and they grip forever. I wouldn't recommend a 45 sidewall on this chassis though, very little clearance. You have coilovers so thats the main benefit, as 245/40s will fit easier. That will be what I go with next, either a 245 or a 235 on 17s.

18s, I had 225/45s and they gripped semi-well, but the wheels were right around 19-20 lbs a piece, not what you'd want for performance driving, and harder to get a bigger tire on our small cars with no wheel well clearance.

I like 17s, offers a good variety of sizes of tires. Plus they clear my brembos, which also are used trackside

 

[012.5RS]

I'm an expert by no means, but I myself am currently building a 95L for autox which causes me to also worry bout low rotational mass and unsprung weight. Now obviously I will not be doing full blown road course right away, but hope to in about a year or two. I dont believe a 245 would be neccesary with the power youre putting out, especially with the low weight. My car is currently at 2500lbs without my fat self. I plan on running a Dunlop Direzza Z1 225/50R16($590/4 with road hazzard prior to shipping) on my 16x7 +53 volk te37's that I have. Now my decision has a lot to do with the fact that I already have these wheels from my previous rs, theyre light as hell at 12.2lbs each. I do eventually plan on jumping up to a Dunlop Direzza Z1 245/40R17($790/4) on a 17x8 +45(15.6 each) Enkei RPF-1. From what ive read the Dunlop Z1 tends to out perform the Hankook R-S3 on lighter vehicles. Both of these tires are rated as extreme summer tires and are a cheaper alternative to R-Comp's obviously. I hope I've been of some help. And obviously anyone with actual track experience would be able to give you more and possibly better information.

 

[livinglegend629]

I asked a similar question not too long ago, got some good responses as to what tires to use.

http://www.rs25.com/forums/f9/t171347-your-opinions-best-tire-tracking.html

From the information I've seen, for our cars 17 in is prob the best best, most of the guys I've seen having a 16 or 15 inch tire are usually in smaller/lighter cars like a miata or ek civic.

 

[Z1 Performance]

1. define track use...everyone has their own definition of what track use means to them

2. tire size is a virtually useless number unless it is referenced to a specific tire. A 225 of one brand can be vastly different in physical dimension than the same 'size' from a different brand. What's more, R comps tend to run much bigger than their street tire counterparts, even within a given brand

3. if you want to keep things as close to as they are, then stick with the same overall rolling diameter as what you currently run. Any change will change the balance, perhaps for the better,perhaps for the worse, and again, it's very tire specific and car specific. I remember a long time ago getting S03's for my 350Z because they worked so well on the Subaru's and Evo's. I ripped em off within 1000 miles, they were horrendous. Way too stiff, grip was ok, but nothing spectacular. Swapped them to a set of Toyo T1S and was much happier. Every bit as grippy on that platform with my setup at the time, and much more comfortable as well. Same goes for track tires. I've run cars with A048's and loved them. And then found R888's to be better on other platforms/setups. It's trial and error and unless someone has your identical setup, it's nearly impossible for anyone else to tell you how it will/won't act

4. gotta define the budget with #'s. You can spend $50 a tire, or 5x that. Same goes for wheels with an even greater disparity. Light wheels in and of themselves are not the be all end all. It depends where that mass is centered. A grippier tire on a heavier wheel is generally preferred to a less grippy tire on an ultra light wheel.

 

[Monster]

Just based on the amount of tire choices 17s are what I suggest.

17x8 - 8.5 would be perfect as you would be able to run 215-255 comfortably without too much negative effects.

 

[thumpetto007]

1. Track use... Gingerman and Waterford Hills racetracks in Michigan. This car will be the first one I've driven on a legit track, and I plan on learning my car until I can reach 10/10ths.

2. Tire... I have only used not-so-grippy street tires (toyo proxes 4, bf goodrich g-force, some federal sports compound...) so I don't have much experience in the tire department. Looking in random forum threads, a few common tires come up a lot... Star Spec, R888, RS-3 (I think) I have also read (or been told) that I should get a few sets of crappy tires to start racing on, to better understand my cars balance at, and after the limit.

At the same time, though, I'd like to dedicate a rim and tire set to only the track. So I'm not opposed to a R compound, at least eventually.

3. I was hoping to get vehicle specific information, (2.5rs, 25.125 inch ride height (ground to top of stock fender arch) -2* camber all around, corner balanced eventually) and I guessed that there weren't a large variation in tire choices for our weight and suspension geometry at the track.

4. I have a 1400 dollar budget for rims and tires. I usually can get rims/tires below list/retail prices. Lets just say 10% to keep it simple.

 

[SubieNate]

I've run 225/50/16's on my car for a while now and their sidewall deflection IMHO is a bit much. I would prefer a 225/45/17 or wider 17" tire.

Grip wise the 225/50/16 is okay, but they tend to wear funny because of the increased sidewall deflection (more wear on the edges when driven hard as the tire rolls more) and the feel is not as good under hard driving. Ultimate grip is okay, but transitions aren't great and the tire just doesn't feel overly precise, especially on center when compared to a lower profile tire.

This is all from my personal experience just driving hard on back roads... some more informed than I may disagree. FWIW.

Nathan

 

[thumpetto007]

What about a shorter sidewalled 16 inch tire? Or even 15 inch... I guess they'd look silly, change the gearing of my car and balance. I'm kind of curious, though.

 

[Z1 Performance]

gotta run a tire calculator and then see where it puts you and if those changes are something you can live with. In my experience such changes are great when you have a specific tire setup and goal in mind..rather than throwing it against the wall and then being forced to live with the consequences (assuming budget isn't endless to just start experimenting)


we have a killer deal on the Toyo R1R right now:

225-50-16 – $569 shipped for the set of 4
235-40-17 – $589 shipped for the set of 4
245-40-17 – $699 shipped for the set of 4

 

[freeride]

17" (good tire width selection and can clear brakes when you upgrade)
245-255 tire width (without major fender mods)

even tho you will have a dedicated rim, I would start tracking on a non R compound tire get some good seat time on those then when you feel you maxed out those tires then move to a dedicated R comp.

Spend the money on a light 17inch rim, then get something along the lines of a (star spec) I run them, most others do to. Great tire for the price.

 

[thumpetto007]

Thanks for the input, guys!

Z1 Performance, no thanks on the tires! I appreciate the offer, though.

 

[Murphy2012]

Here's my .02. I have an 01 RS which was around 2750lbs with me in it last year, it's probably dropped about 80 lbs in the off season. I run 275/35-15 A6's on 15x10 wheels for Autocross and 245/45-16 Hankook Z214 Road Race Compound on stock 16x7 6 spokes for hillclimbing. If I was running track days alot, I would go to a 17" setup as it would be beneficial for gearing, probably RPF1's with 245 Hoosiers. It really depends on what you are looking for. The autocrosses in my region are mostly short courses that I have only shifted into third once on, which is why the 15's work great, lower gearing. I need a little bit longer second and not so much tire on the Vermont hills (lots of crown and cracks) so I am trying the 16's out this year, and will probably run them in the COM event(s) I plan to run this year at NHMS.

 

[thumpetto007]

Thanks Murphy

I forgot about this thread...

I've decided on 245/40/17 Hankook Ventus RS3 heat cycled tires and 17x8 Enkei RP-F1 rims.

I've heard that the RS3 is a consistant tire to use on the track, and 245 width so that I can (hopefully) break traction and develop a feel for my car.

 

[Monster]

good choice!!!

 

[djdoc36]

17" (good tire width selection and can clear brakes when you upgrade)
245-255 tire width (without major fender mods)

even tho you will have a dedicated rim, I would start tracking on a non R compound tire get some good seat time on those then when you feel you maxed out those tires then move to a dedicated R comp.

Spend the money on a light 17inch rim, then get something along the lines of a (star spec) I run them, most others do to. Great tire for the price.

What this guy said....smart smart smart smart!!!

 

[osakarory]

How do you get such a wide tire on without fender mods? I am constantly hearing people say that anything wider than 215 will cause rubbing in various areas. Hell, a guy I just met racing his 2door GC8 runs 205/50/R16s because he said 215s on 17s rub.

 

[thumpetto007]

Proper offset rims, negative camber, and aftermarket struts.

I didn't rub on the fender or the strut. 215/40/17 ZII tires, 17x8 +48 (I think) rims, -2.3*/-1.8* camber F/R, budget coilovers