72 GTO 19in Front 20in Rear, PLEASE ADVISE

[andre.72gto]

Hey Guys!
I just purchased 72 GTO. Would like to know what im able to install on my car without going in to major modifications. I would like to have front 18in and rear 20in
What would be the widest setup i can do?



Please see pictures for the reference.
Also if there is a thread already please share a link.
Thank you very much!
Andre

[csouth]

I can tell you to scrap that first car as a reference unless you are running an aftermarket chassis. That car was built by Speedtech and is on their Extreme chassis, so wheels that fit it will not fit a stock setup. The second car I'm not so sure of.
Without know if the 72 has an odd shaped wheel opening in the front, safe bet is 18x9 and 20x10.

[boss_hoss]

I'm Running Foose legend 18X8 4.5 bs with 245/40r18 up front and 20x10 5.5 bs with 305/35R20 on the rear. The rears were really tight but I rolled the fender and now were good to go. You can get a more clearance with a little more BS but I haven't had any rubbing issues so far. Note you ll see between the two photos I changed to 2" lowering springs instead of 1" springs after installing these tires as they are fairly tall. This probably wont be my long term set up but its not bad for now.

[csouth]

Yeah, safe rear backspacing on these is usually 5.75 on a 10" rear wheel.

[andrewb70]

I have a 70 GTO, which has the same wheel wells as a 72. I run 295/35-18s in the rear on 10.5" wheels with 6.25 inches of backspacing. They never rub, and neither did the 295/40s before that, or the 294/45s before that...Personally, I think the max tire diameter that looks good on these cars is 27".

In the front I currently run 274/35s on 9.5" wheels with 6" of backspacing. They rub a little on the sway bar at the extremes...On the front a good size diameter is 26". This makes for a nice balance with a 27" tall rear tire.

Andrew