Just like the title says, I'm wanting to up 315/30/18 BFG drag radials on the back. What's the recommended width/offset needed to clear the fenders? I'm willing to to roll them if I have. Thanks.

 

I don't know if anyone has done that yet. I had 295/35's on 10.5 and from that experience and checking tirerack for bfg's I would say minimum 11" rim with around a 35 offset. You will have to roll the fender. Are you lowered? You might consider a narrower tire with taller profile.

 

Who makes a rim that fits the Z 11" or wider?

No, I'm not lowered and don't really plan on it.

 

They have people stuffing 315s on 9" rims.

Why run 11s?

(Honestly I don't know. I know that for a 10" rim the native size is like 285 or so, but I don't think there are many 11" rims out there... I was wondering what the trade offs of running huge tires on smaller rims was.)

spdkils

 

These should fit on SSR Comp-Hs (10.5) with little problem. I have 295s now and there is gobs-o-clearance fornt and back. For a drag setup the SSRs are a good choice , light and not expensive. an plenty strong gneral use (just be wary of (pot holes) . you can getem at Tirerack.

 

These should fit on SSR Comp-Hs (10.5) with little problem. I have 295s now and there is gobs-o-clearance fornt and back. For a drag setup the SSRs are a good choice , light and not expensive. and plenty strong general use (just avoid (pot holes) . you can getem at Tirerack.

 

If you look at tirerack, it recommends an 11-12" rim for the 315/30 BFG drag radials. Its one thing to stretch a street tire to make it look cool or whatevery your taste is, but a drag radial, to perform well should be on the appropriate sized rim. Sure you can stuff an 315 on a 9" rim, but the performance will suck.

I like the SSR's too. Another choice is CCW, good, light strong rim. Can get custom offsets and easy out ring replacement if you do damage it. I did not have a lot of room with my 295's. I rubbed the shock on very hard cornering. Make no mistake about it, 315's are going to be a tight fit. Doable, but tight.

 

If you don't have a price concern... I'm sure you can call up some reseller, and nab a wheel built to order.

The 10.5" SSR wheels come with a +43 offset, I figure an 11" would come with a few mm higher.. Maybe 47 to split the differnce.


spdkils

 

Volk makes the GT-C in 18x11 +20 I think.

 

not that i know more than you b/c ive seen your posts and you seem really knowlageable track guy but i dont understand why you would think that can you explain? Wa2good runs 315-30-18 on the track on nismo rims 9.5 and has had good results on the track i dont see how having a larger contact patch would decrease performance

 

There are two reasons I would not run a greatly oversized tire. One is the side wall will be weaker when its at an extreme angle. A weaker sidewall will hurt turn in, and make for uneven weight transfer. Giving the car a mushy unstable feeling in corners, compared to a properly mated rim/tire.

And the second reason is that by putting an oversized tire on, you will bow the contact patch. Bowing the contact patch effectively makes it smaller and less grippy than a tire mounted on a properly sized rim. It also will unevenly distributing heat across the surface. Very likely that the tires get "greasy" and wear quickly on a setup like that. So the tire may be that big, but since its bowed the car is not able to turn all of it into traction.

Wa2good has an incredibly high powered track car and he may be willing to make that trade off. My personal opinion is that the car would have more grip with a well mated tire and rim combo. But that's just opinion.

 

You really can't beat the SSr Comp-H ffor light wiegth +low cost. Most other options mentioned in this thread eier are way to narrow or cost way more. Mounting a recommended 11" tire onto a 10.5 " rim is a non issue. Mounting a 315 onto a 9" rim shoudl make one take pause. Inorder to get a flat patch you nee to under inflate , which in turn make the sidwall very weak.

Anoter think to take into account , you loose a little clearance when running true coil overs in the back. A spring , shock and sway setup buys ~.5 inch for the backside tire mounting.

 

Actually I bet you could beat that combo for the price. I have the track edition and I'm doing what a couple people on this board have done, putting the stock rear 8.5's in the front and the getting the front 8's widened to a 10.5 or 11 and running either 295 or 305's. With that 11 you could run 315, but thats a lot of meat in the back that I'm not using since I'm N/A. Anyways, a 19lb 11" wheel that you get made for $350 is not bad at all. That's my plan anyways.

 

pm racin (Nick @ N-Tech Engineering.com) He runs an 11' rear w/ wide racing tires = to ~ 305mm. He didn't have to role fenders (he's setup for speed, not looks, i.e. there's plenty of room for the proper wheel/tire setup.)

 

Uhhh..This is with a MODIFIED 9" wheel. You should know 315 on a 9" wheel is ****ing ridiculous and just does not fit.

A 11" wide wheel with around a 28+ offset and a 315 tire should have no clearance issues.

 

From another thread
link to said thread
https://my350z.com/forum/showthread....2&page=2&pp=20
not trying to start no **** i just want to learn before i spend my 1K+ at tirerack..

 

I really like the SSR Comp-H, where would I take the rears to have them widened from 10.5 to 11 inches, and roughly how much? Or would I be okay with 315's on the 10.5 with +43 offset?

Thanks for all the input so far guys.

 

I'm sure people run that all the time, but they also have -5 camber to make it fit under the fender.

 

10.5 is plenty for a 315! look at all the '03 '04 cobras.....they all run 315 dr's and i believe their stock wheels are 10'' in the rear

 

What did you ever decide on? I just purchased a used 2003 Track Ed. 350Z that I want to take out on road course tracks for Driver Ed. and seat-time days. Car only has 9800 miles on it!

zillinois, what type of wheel do you run out on the track? What size (widths) front and back and what size and brand tire?

Not meaning to hi-jack this thread so PM me if this is too far off topic. Thanx!