Maximum Tire Size on 1986 GN Stock Rims and Possible Rim and Tire options

[Caffeine27]

I just purchased a 1986 GN and have the original rims on it. I want to know what the maximum tire sizes I can have on them. Also what would be the maximum rim and tire size that would fit on this. Last question, can you do staggared sizes on a 1986 GN.

 

[V6sleeper]

Usually 255-60-15 fits best on the rear 7" stock rim, some push it to 275/60 but its not recommended on a 7" wheel only 8" and wider

I wouldnt go larger then a 17" rim but thats just me

 

[1986 Buick GX1]

Probably the most popular wheel combo is the 18”x8” and 18”x9 Gbody GNX replicas with 255/35’s on the front and 285/35’s on the rear.
These work very well with stock and some brake upgrades.
Some of the more aggressive brake upgrades push the wheels out far enough to rub or require inner fender modifications.
It’s best to measure your setup to be sure.

GNX Reproduction Wheels Rims, set of 2 18" x 8" and 2 18" x 9", GBodyParts.com

 

[Caffeine27]

If I don't want to upgrade the brakes, what is the best wheel and tire combo? Just want to keep car stock except for wheels and rims.

 

['87 Turbo "T"]

Sounds like a personal preference.

Can go up to 255’s in the rear. Some will push a 275 in the rear(need a wider rim for 275’s IMO). I run 275’s in the rear on an 8.5” rim. I run 235’s up front with no rub. That doesn’t work for all.

I’m still running on 15’s.

 

[V6sleeper]

If I don't want to upgrade the brakes, what is the best wheel and tire combo? Just want to keep car stock except for wheels and rims.

There is no best, there is lightest, there is most expensive ect, but its what you visually like the best..

Most of my Gbody's have 15x7s on the front and 8s on the rear, and only light aluminum's whether it be welds or Convo pro's

Its up to you what look you like

 

[dynoman]

Last question, can you do staggared sizes on a 1986 GN.

Yes . some run 17" or 18" fronts with 15" rears .
You can check many combos in the sticky " OFFICIAL: wheel/tire picture thread" in this part of the forum .

 

[dynoman]

If you want to run bigger brakes up front it is easier to do with 16" , 17" or 18" wheels . I had to measure very carefully to make sure my 12" 6 piston Wilwood fronts would fit inside the 15" rim .

 

[1986 Buick GX1]

If I don't want to upgrade the brakes, what is the best wheel and tire combo? Just want to keep car stock except for wheels and rims.

As others have said, it’s personal preference.
Gbodyparts has a few different wheels designed for the regals.
Some like the cheapest that fit, some like a drag race look, some like the pro touring look.
I had to go tubular upper/ lower A-arms and aluminum spindles to get the size and look I wanted.
I will be making some GNX style fender cut outs on the front for clearance.
The rear fenders are already rolled to make room.
The body will be moved to the passenger side 3/8” to get it centered while installing body bushings as well.
My fronts are 18”x 10” with 285/35’s and the rears are 18”x 10.5” with 295/35’s.

1” taller upper ball joints help pull the tops of the tires in on compression for more tire clearance as well as improve handling.