04 GTO wheels on Grand Prix

[85GPLEf41]

Hello, i have a chance to pick these Falken rims and semi new tires up at a reasonable price:
https://static1.pt-content.com/images/noimg.gif
The guy who is selling them doesn't know the specifics other than the tires are either 235 or 245... SO i was wandering if these are remotely close to fitting on my 85 Grand Prix. They came off a 04 GTO so i think the bolt pattern would work right?? I tried researching the numbers but no luck.....

[Apogee]

2004 GTO should be a 5x120mm wheel pattern whereas your 1985 GP is 5x4.75 [5x120.65], so they're not the same. Close, but no closer than a BMW wheel pattern. If you do a search on "BMW" in the Wheels and Tires forum, you'll get a ton of threads asking "Can I run a BMW wheel on my GM car" and you will get most if not all of the opinions on the matter. To do it correctly, you really should have matching wheel patterns in my opinion, whether that be with the use of an adapter, custom hubs/axles, etc.

I don't know where the GTO wheels are with respect to backspacing or offset, but maybe someone else will chime in with that. Does the seller not know whether they're 235 or 245 tires? Can he not read a sidewall or send you a picture of it? The wheel offset should be cast or stamped into the mounting pad of the wheel.

Tobin

[85GPLEf41]

The guy couldn't seem to remember any specs when asked. He just told me to check them out because they are at a friends shop. I have been reading conflicting threads on the bolt pattern:confused: Some say yes and some no, so i figured I'd ask for any opinions. I was kinda of hoping they would cuz my car needs to move more than in and out of the garage:)

[Apogee]

That's the thing about asking for opinions on something like this, some people will say go ahead and run the 5x120mm pattern wheels on a 5x120.65 hub, others will say the opposite. How much weight you give to complete strangers' opinions on the internet is up to you.

If you've been reading past threads on this same topic, hopefully you've found Matt's (aka silver69camaro) thread (https://www.pro-touring.com/forum/showthread.php?t=50804) where he posted up the FEA stress analysis comparison showing the negative impact of introducing the bending component caused by the pattern mismatch. It's quite informative from an engineering perspective.

Tobin
KORE3

[85GPLEf41]

Well that's the reason i originally posted this question up was to get a more definitive answer from the experts. Or at least from those who have attempted it before. :) Thanks by the way....So i guess i will forgo those rims and tires and keep an eye out for something that does fit properly.

[NASH JUDGE]

you will need spacers / adapters. The bolt pattern is close but not the same. those wheels have a 6.25 BS and the hub on them is probably smaller than your GP's. To do it right, get proper thickness spacers and hub and wheel centric adapters. You want the hub and lug nuts to take the load of your car not just the lug nuts. Tires might be a little small for your car but will work. I dont know the max size tire that 8 inch wide wheel will take. I have some 04 GTO wheels that I want to put on one of my older GTO's too.
Those wheels will look good on your car. :usa:
Get em on and post some pics.