Big Rear Tires

[clintmopar]

I have a 68 Road Runner with a stock 8 3/4 rear-end. What is the biggest rear wheel/tire combination that I can fit without any mods to the car?

 

[D575]

I have a 68, 15 x10 , 4/12 back space 12" wide tire

 

[hunt2elk]

I have a 69 RR and tried to get 15x10 with a 295/50 under it. It wasn't possible with the stock suspension. I ended up with a 15x8 and 275/60's. I suppose a guy could with air shocks, but that isn't for me.

 

[old_skool]

I currently have 275/60's as well, with my 71, I didn't care about stock, added shackle extensions and air shocks, and put on old school bias pro tracs N50/15's
not a clear picture, but you get the idea...

here's my 275/60's, but I also have keystone rims on, not sure of the back spacing.

 

[Budnicks]

I have 295-50-15's easily fit with more room

Ride height can determine some fitting issues, my car is somewhat low, the farther you go up into the wheel well the more it tappers in toward the top on the outside.... I have 295/15/15's Radial Ta's under my current 68 RR in the rear have probably near 3/4" on one side don't remember which off hand & 7/8" at the inside between the leafs & the tire bulges/girth, & appr. 5/8" on the outside of one side & 1/2" on the other side of the car, where the trim goes into the wheel wells. they're 5.25" BS 9.5"{actually 9.200" where the tire mounts, from actual outside to outside of the wheel is a little over 9.5"} X15" Halibrand Knock offs, probably more like having a 9" wide wheel, made by & for "Edelbrock" quite a few years back, probably 10+ years ago now... I've had 315 M/T drag radials on my other old 68 RR {sold a few years ago} with rolled outer lips & stock length hosing/drums 15 x10" American Racing wheels with 5.5" BS {might have been 6"BS} IIRC ??, no rubbing issues with the correct ride height... I suggest to buy a "Percy tire fitment tool", from like Summit Racing for appr. $70, you will be able to get & order exact size & BS wheels for your specific combo... mine isn't done yet sorry for the poor photos too... Good luck

 

[BIG-A]

On my '70 I had 15X8 with 4.5" back space and 275/60/15 street tries. They fit with plenty of room and no rubbing or modifications what so ever. I then bought 15X10 with 5" back space and 325/50/15 MT drag radials. For these I had to trim inner and outer wheel well to prevent rubbing and I'm also running super stock springs. I would take a guess and say that 295 would be pretty tight with stock ride height and no modifications.

 

[Budnicks]

oh yea, welcome to FBBO

 

[Bkl89]

On my '70 I had 15X8 with 4.5" back space and 275/60/15 street tries. They fit with plenty of room and no rubbing or modifications what so ever. I then bought 15X10 with 5" back space and 325/50/15 MT drag radials. For these I had to trim inner and outer wheel well to prevent rubbing and I'm also running super stock springs. I would take a guess and say that 295 would be pretty tight with stock ride height and no modifications.

View attachment 180848

Hi your car looks awesome! I'm thinking of getting the 325/50's.. In your picture what tire is on your car? The 275's or 325's? Thanks