18" wheel offsets for wider tires
 

I'm ordering wheels and need assistance on offsets. I'm current on H&R springs. While I may change that over this year, I'd like to get a set of wider wheels to run wider R888 tires. I'm thinking at least 305's, if not 315 or even 325 if they will fit. I'm not worried about rolling the wheel fenders. But I don't want to mess with anything else. I'm looking for 18x9 and 18x12 wheel sizes. What matching wheel offsets and tire sizes in 18's will be best? Keep in mind that I want to maintain the factory proportions between the diameters. I know both camps get fierce, but my AWD works well and I'd rather not chance. Eventually I drop the front diff, but only after I splurge on an LSD. THANKS ALL!

WhereItsAt

they dont make 305s or 325s for 18s.
your options are 315 or 335s.

you will be fine with 315s on any 12" wheel regardless of offset..
335's are another story, you'll be super close to the fender or inner lining. 18x9 wouldnt make sense.

i assume you'll be doing a 235 40 front for the whole awd thing.
running a 235 on a 9" wheel will stretch the sidewall.


i actually confirmed this myself this past weekend. we had a 235 toyo r888 on a 9" wheel, and a 315 on a 12" wheel. 1 full rotation was measured at exactly 80.0". run a 245 40 18 up front if youre going 9" otherwise stick 8/ 8.5 and run gt2 spec sizes. 235 40/ 315 30

Thanks Steve. What about offsets, assuming 235x40 and 315x30?

im not sure. but i ran a 235 / 315 setup on my OEM 18s back in the day and i didnt have an issue.

i dont know what offsets are fine, but i'de bet that ANY offset is fine. virtually every aftermarket wheel will have a more aggressive offset compared to turbo twists, which pretty much guarantees you wont rub. (rubbing on our cars is usually on the inside fender well, not the outside)



what kind of wheels are you thinking of getting ?

Nothing expensive. The forgeStar F14's.

gt2 wheels are 8.5x18 ET 40 front, and 12x18 ET 45 rear

gt2 fitmet f14's.
https://www.6speedonline.com/forums/...2&d=1370089623

look at the shadow over that rear wheel.. PLENTLY of room to spare ... if forgestar allows for custom offsets, i'de go 40 rear.

they do make a 305 for the 18s.... he would have to step up tire size in front too tho.

305 35 18 yes.
waaay taller than OEM, and will slow him down, unless he's making 800+

800 + whoa? u sure about that? i been using a 305/35 tire size since i was making 650 +:rolleyes:

I won't reinvent the wheel(pun intended) and get the factory gt2 sizes. Prodigymb, what are your wheel dimensions? Tire sizes?

mark, you know what our dear leader said about 305 35s at the mile.

Steve, that's the look I want. Thanks!

pridigy is rwd. he's running a 16" ccw drag set up now.
he ran a 305 35 18 rear micky thompson on super light weight hre's.
he likes brisk walks on the beach, and speaks of himself in 3rd person.

whereits at.. add 5mm to the offset (making it a 40). trust me. r888's run a teeny weeny bit tall and have a squared sidewall. what this means is that the wheel will look tucked in. i have r888s on a 12" myself and i run a 7mm spacer in the rear.

here's a 335 on a 12" forgestar. crazy huh ?
https://www.6speedonline.com/forums/...ine=1389817135

I have used 295/30/19, 315/25/19, 315/30/18 , 305/35/18, 295/45/17 and now I use 315/45/16 on 16x10 lol

https://www.6speedonline.com/forums/...ine=1389817096

hilarious