Another "BS" Question...

[rosadod]

I'm looking at a set of wheels... the fronts are 8.5" wide w/ a 20mm offset and the backs are 10" wide w/ a 30mm offset. I plan on lowering the car 1"-2". I don't want to notch or roll, how wide of adapters do I need so I don't rub either way with it lowered?

 

[BlackMetal]

That's a pretty excessive positive offset, those wheels are probably designed for FWD applications, with a very shallow lip and a lotta backspacing.

The BS on the 10" rim is about 6.68" if I remember the formula correctly. You'd probably want 2" wide adapters to bring it down to 4.68". Usually when people do 10" rears, they go with a 4.75" backspacing, so you'd be pretty close.

8.5" fronts is fairly wide, I'd be worried about rubbing. The BS on that one is about 5.53". Probably a 1" or 1.25" thick adapter for those. But I think it'll rub regardless even if you space it correctly.

But as I said this all depends on if I'm remembering the formula correctly, which I think I am.

To calculate backspacing you use this formula:
(rim width ) / 2 + 0.5 + (offset /25.4) = backspacking
Some people use that formula without the "0.5" in there, it's just there to prove a half inch of slack in your results.


Being 100% with the calculations is pretty hard to do, there are little variables with each wheel, so if possible, you'd be better off ordering wheels that are made to fit our cars.

 

[rosadod]

What BS is needed in the front? Any suggestion on an 18" or larger wheel with a closer BS to what we need?

 

[BlackMetal]

A common backspace for the front is 3.5". I was going to try an 8 inch wheel with a 3.5" BS but people said it would stick out too far and rub the fenders, so I got 7".

American Racing is a good bet for 18" or larger designed to fit American RWD applications. CenterLine has some 18s as well.

I also forgot that you mentioned dropping the car 1 or 2 inches. That makes fitment even harder. Having 8.5" wide fronts and 10" wide rears is enough of a squeeze if you keep your ride height at stock level or above, but lowering the car makes it even harder. If you want wheels that wide but want to lower the car, it's not going to be easy. You might have to notch the frame to get the 10" rears to sit far enough under the car to not rub if you're going to lower it. I bet the 8.5" fronts would rub on sharp turns even at stock ride height, definitely will if you lower the car.

I have no experience in lowering my car, perhaps someone else can give you better advice on how to cram some wide wheels under a lowered body.

 

[GNXwannabe]

I am bolting on a set of Ruff Racing 18x9.5 rear with 20mm offset and 1.25 adapters that give me a backspace of exactly 4.75 inches with 285/35/18 Nitto 555 and 18x8.5 fronts with 20mm offset and 1.25 adapters that give me about 4.00 backspace with 245/40/18 Nittos. I test fit the rear wheel only this evening and it was VERY close. The tires get mounted in the morning and I will let you know if they fit. I did bolt on a set of 275/40/17 (Halibrand Cobra III 17x9 Chrome Deep Lip) with 4.5 backspace today with plenty of room to spare. The Halibrands with Fusion 275/40 rear and 245/45 front will be for sale (Brand new Wheels and tires) if the Ruff Racings mount up OK.

 

[rosadod]

So how'd they fit?

 

[GNXwannabe]

Fit is good on both sets. The 18x9.5s on the rear with the 285/35 is CLOSE to the frame. I will probabley go with a 1.5 spacer. I also think the car will look and sit much better with a little drop (1-1.5"). I converted the bolt pattern from 5 on 4.75 to 5 on 4.5 this offers a much better selection in wheels due to the fact that most of todays 4.75 wheels have too much offset. The larger offsets do not leave much "lip" on the outside of the wheel and I don't like the FWD look on these cars. I will post some pics to get opinions when the weather breaks (snowy and nasty the last couple days)

 

[rosadod]

Which Ruff Racing wheel did you get? There's a bunch of them on eBay.

 

[GNXwannabe]

I went with the 278 with black centers. I have a friend with a wheel shop here local that hooked me up. I like the 278 because it has a "stepped" lip meaning it does not have the "smooth" tuner looking lip. The stepped lip is closer to the wheel styles of the 80's with a modern center.

 

[GNXwannabe]

Took some pics today. Can't get them to post. Anyone interested I can email them.

 

[rosadod]

Yeah... email the pics to me danielrosado@yahoo.com. Thanks.

 

[BlackMetal]

So do the front 8.5s rub at all? I'm curious to know, I bought 7" wide fronts because everyone told me 8s would rub, but I wish I had the deeper lip of the 8s.

 

[GNXwannabe]

NO RUBS on the front (lock to lock)! REALLY close to the frame on the rear. I am going to drive it a little and if it does not touch I will leave it because they tuck in really well.

 

[BlackMetal]

Hmmmm interesting. I get a little bit of rub at full lock with the 18s that I use now, so when I bought my new wheels I went back to a 7" wide for the front. But now they look to small, I think I'll exchange them for 8" wide again.

 

[GNXwannabe]

Here are the RR 278s OPINIONS?

 

[GNXwannabe]

How about the Halibrand's?