Need Some Tire Size Help... Please. 18" Wheels

[UMI Performance]

Hello Everyone.

We decided on Boss 338 wheels for the our Monte Carlo project- viewtopic.php?f=5&t=40563&hilit=umi#.UQf8ZvIkQ04

Right now we planned on a staggered size:

Front: 18" x 8" w/ 4.5" Backspacing
Rear: 18" x 9.5" w/ 5" Backspacing (Rear disc brakes)

Car will be lowered 2" in rear and 2-2.5" in the front.

What would you recommend for max tire size and tire height? I talked to Tony_SS and he is running 245/45 up front and 285/40 in the rear on the same width and back spacing but 17". Anyone running a 295 in the rear?

On the front, is anyone running wider with a spacer? We tried a 255 with the same back spacing and it hits the sway bar, it's a stock sway bar too. So we are wondering if we can go wider with less back spacing (ie a spacer)?

I am waiting on longer studs and lugs to come in to actually sit the car down on 255's that we have on another set of wheels.

Just looking for some opinions on others setups. Thanks!

 

[pontiacgp]

What rear end do you have in the Monte? The width of the G body rear is narrow I would think the 5" backspacing on the 9.5" rear rims would put the rim close to the frame rail

 

[UMI Performance]

What rear end do you have in the Monte? The width of the G body rear is narrow I would think the 5" backspacing on the 9.5" rear rims would put the rim close to the frame rail

Factory rear end. But we will be running rear disc brakes which will widen the track width so that is why the back spacing is more.

Tony_SS said he is running 285 rear with 5.5" back spacing and a 12mm spacer... he is running rear disc brakes as well.

 

[pontiacgp]

the rear I have is 1.25 wider on each side than a G body rear. I have 16x8 wheels with a 4.5" backspace. With 245-50 tires they just touch the quarter panel lip on heavy bumps or lard *ss friends in the rear seat. With those wheels and tires on a G body rear there is 1/4" from the sidewall to the frame rail