Pontiac GTO Forum banner

65 GTO 15" Biggest Rear Wheel and Tire Recommendation

11K views 48 replies 9 participants last post by  Baaad65 
#1 ·
HI Folks,

If you could recommend biggest 15" Rear Tire & Wheel combination for my 1965 GTO?

Look for the widest, fat rear end look without modifying the rear fender lips.

Thank you in advance.
 
#2 ·
I have 275/60/15 MT drag radials on 15x8 rim's on my '65 with 3/4" spacers under the stock springs and it's tight but no rubbing on bumps, like the stance without the spacers but the tires rub on larger bumps so when I get it painted I'm going to have them make some more room in the well. Would someday like to run 17" so it looks more modern.
143216
143217
 
#8 ·
Idk because there's only maybe an inch on the inside from tire to frame, and idk if there was a choice on the MT website but these were the most popular setback and got them through Ebay...I didn't know how to check setback and my tire person wasn't much help, he said to buy 255 that 275 would never fit so that's what bought first then when we mounted them he says I could've went bigger, I wanted to strangle him because then I couldn't return the tires after they been mounted so had to sell them for half and bought 275. Then when you installed the 461 the Sportsmen's had no traction so changed them out again to the drag radials and giving away some more tires, I'd really like 17" but the tires are slightly larger and they reccomend a 9" rim over my 8"s so they would never fit until I make some room in the wheel well but maybe with a 5" setback it's a possibility I just need a good way to measure things and a bunch more money...I'll work on making these tires bald 🤣
 
#9 ·
Anybody out there have 17" wheels on their goat and what size tires especially for a '65? Like to do the front too but got to watch the clearance as I'm running 215/70/15 now with 1" in lower springs and the just clear everywhere even on big dips and bumps. Guy that did my alignment said wider tires up front would wander...you know I just kinda didn't put a lot of thought to sizes as I just got back into the game after 30 years on the sidelines and thought 15" was a big upgrade from 14" but after a couple years going to shows my 15" tires look like balloons but I'm not crazy about the 20" and up look on 60's cars. I want to stick with the same wheels and they only come in 15" and 17".
 
#20 ·
Good information, I'm running 8" rims in back 7" up front, if I want 17" rims the only 28" tall ET SS drag radial recommend a 9" rim and the tire would be a 305/45/17 pretty big and I would definitely need some wheel well massaging but I want to stay with 28" tall so my rpms don't get any higher at highway speeds.
 
#22 ·
I wanted the same look your talking about, and I went with 15/8 Weld Racing wheels with 4.5" back spacing, with Mickey Thompson ET Street Radial P255/60R15s. I bought them while I still had the body and frame separated. I measured everything 6 ways to Sunday, and I should have an inch clearance inner and outer. I'm still in paint and assembly mode, so the suspension hasn't settled yet. I put 15/4 Weld Racing wheels on the front, with Mickey Thompson Sportsman Radial 26x6R16LTs.
I'm guessing you've already researched it, but Eastwood has a device that will roll the lip to help with clearance. IMHO that would be more desirable than grinding the lip. Go to their site and search for Fender Roller. I'll be considering this if I find my measurements were off.
Tire Wheel Vehicle Car Hood
 
#24 ·
Did you get a pre '68 or '67 I believe 12 bolt because I remember the '65 rear is 1" narrower and that will give you clearance problems also I ground the wheel well trim down to the actual well about an 1/8" ,every little bit helps but I'm having clearance issues up higher in the well where it bumps out and there's two layers so I'd like to have that heated and planished in some when I get it painted then I can take the 3/4" spacers out and it looks good but like I said it will rub on good bumps. I'll have to check out the setback or offset of mine and maybe changing that would help, American Racing has a good measuring guide on their site...still like the look of 17" wheel on their visualizer.
 
#25 ·
I don't know. The dimension you should be looking at is the section width, which should be the measurement from sidewall to sidewall. If you go to Jeg's website and enter 672-3452, you'll see the tires I bought. Scroll down to the details and it shows the section width as 10.2". Do the same thing with 672-3453 and the 275s will come up. The section width for the 275 is 11.1". That's a little too close for me to take the chance.
Thanks for the compliments! My car is going to look even better when I pop the hood. Check this baby out. 1972 455 HO, 7F6 heads (round port), solid roller cam, roller rockers, dual quads. Built to put out more than 500 hp. Can't wait to hammer down on that baby!
Motor vehicle Automotive design Automotive exterior Car Auto part
 
#26 ·
Very nice !...throw back wires too, these cars just weren't made for big meats that's why I'm surprised 275/60/15 fit with just a 3/4" spacer on stock springs. Here's a couple more pix for a visual and believe it or not these two pix were taken within minutes so I don't know why the rake looks so different probably my camera angle 🤨
143368
143369
 
#32 ·
Gotta put some semi-gloss black paint between the fins to bring out those MT valve covers. My engine will be Ford blue because I like it much better than the Pontiac colors. So my finned valve covers got the treatment.

This is where I left off on my build, but this is about the stance I want. It'll sit high in general, with a little more at the rear. Should be able to drop the transmission or change a clutch without needing a jack to get it up high enough. Those prone to nose bleeds might want to refrain from riding along. LOL Got Hoosier 29" x 12.5" x 15" tires and 15 x 10" rims that will go out back.

Motor vehicle Automotive tire Automotive lighting Automotive fuel system Automotive exterior
Tire Wheel Vehicle Car Plant
 
#33 ·
Jim,

In your honor for all you do on this site, the MT covers will be polished up, sprayed blue in between the fins and will have someone engrave "Pontiac Jim" on the flat section of the covers.. I am focused on finishing the body work and get her painted. I will have her in epoxy primer by EOD tomorrow.

The 722 Ram IV heads are the cats arse!
 
#34 ·
Be aware, it's dangerous to try to push the limits on tire fit based on the advice or experience of others. Not because they're "wrong", but because of variances from one car to the next. Keep in mind these things were built on an assembly line by people in a hurry, who might have been hungover or thinking more about the weekend than their job, so the body to frame fitment varied. As long as they could start the bolts, it was good. Also there could have been prior collision damage.

The only way to know for sure what will fit on your car, is to measure your car. There are tools that can help.

Bear
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top