69 road runner max wheels and tires

[69roadrunner383]

I’ve been trying to search the forums, and I haven’t really found a definite answer. My question is.. Front wheel- completely stock suspension, can you run a 15x 8 wheel with 4 1/2 in backspace with a 245/60/15 tire without any clearance issues? And back wheel, completely stock suspension.. Can you run a 15 x 10 wheel with 5 1/2 in backspacing with a 275/ 60/15 tire without any clearance issues? And what would the backspacing be on a 15 x 8 wheel on the rear, with a 275/ 60/15 tire?
No guesses, just fact please. Thank you for any and all help.

 

[Runner 68]

This is a loaded question. All cars are a bit different. There are volumes of information on this topic on FBBO if you truly read the threads. While not specifically about 15 inch rims, this thread tends to push the limit on what can be stuffed under these cars. Read the fine print and your questions will be answered. Any pics of b body with 18” or bigger wheels ?

A tape measure is your best friend.

 

[33 IMP]

I can't tell you what will work on your car. As above, a tape measure is your friend. I can tell you what I used. I had a 235/60x15 on a factory 15x6, with 4"bs, that had no problems. I also had a 10.5/28 slick (pretty sure bigger than a 275) on a 15x8 1/2, with 4 7/8 bs. A 15x8 or 8 1/2 with 4.5 to 4.75 seems to be the sweet spot.
To be honest, I think a 15x10 rim is really pushing it, and the bs would have to be dead on for it to work. Some here have done it, but I don't remember what bs they used.

 

[topside]

I've run 15x8s, 4.5BS (Ramcharger wheels), with 265/50 front & 295/50 rear, plenty of room at stock height or slightly lowered front on a '68 Road Runner.
One current RR has 15x8s, 4.5 BS all around, 245/60 & 275/60s, plenty of room, stock height.
A few guys on Moparts run 15x10s with 5.5 BS & 295/65 ETStreets on '69 RR/GTX bodies as well.
But I'd break out a tape measure & straightedge for that much, as cars can differ 1/4" per side.

 

[69roadrunner383]

Exactly what I needed. Thanks for all the help.

 

[gkent]

Pretty much any tire that will fit a 10" rim will fit with 5-1/2" BS. When it comes to street tires they seem to jump from a 10" wheel to 15" with nothing in between. Try to stick around 28" tall to avoid rubbing at the front wheel opening lip. If you go with an 8" rim on the back then knock an inch off both sides and you'll never have clearance issues. But you'll want to go with a tad narrower tire on that rim. What you have to watch out for using the 10" wheels is the tire cross section. Get something with a 12" or less cross section and you'll be fine - get one with 12-1/2" and you're cutting it close on the inside of the tub.

 

[Black_Sheep]

I've run 15x8s, 4.5BS (Ramcharger wheels), with 265/50 front & 295/50 rear, plenty of room at stock height or slightly lowered front on a '68 Road Runner.
One current RR has 15x8s, 4.5 BS all around, 245/60 & 275/60s, plenty of room, stock height.
A few guys on Moparts run 15x10s with 5.5 BS & 295/65 ETStreets on '69 RR/GTX bodies as well.
But I'd break out a tape measure & straightedge for that much, as cars can differ 1/4" per side.

295/65R15 on 15x10, the only change is the addition of Super Stock springs. They are tight though, before you purchase wheels and tires measure BOTH sides carefully. Clearances can vary a lot from side to side and car to car…

275/60-15 will easily fit any ‘69 B body

 

[topside]

Exactly the car I think of when someone asks about 15x10s on a B-body

 

[hunt2elk]

View attachment 1387479
295/65R15 on 15x10, the only change is the addition of Super Stock springs. They are tight though, before you purchase wheels and tires measure BOTH sides carefully. Clearances can vary a lot from side to side and car to car…

275/60-15 will easily fit any ‘69 B body

If you run a straightedge along the outside bulge of the tire, how much space do you have to the quarter lip with that setup?

 

[Black_Sheep]

If you run a straightedge along the outside bulge of the tire, how much space do you have to the quarter lip with that setup?

The closest gap between the inside of the wheel well lip is 5/8” on the drivers side and 3/4” on the other. The closest point of potential contact is the leaf spring at the back of the tire, slightly less than 1/2 inch.

 

[hunt2elk]

The closest gap between the inside of the wheel well lip is 5/8” on the drivers side and 3/4” on the other. The closest point of potential contact is the leaf spring at the back of the tire, slightly less than 1/2 inch.

I recently replaced the stock 8 3/4 rear on my 69 RR with a Strange 60. It must be a tad wider because I now have 9/16" clearance on one side and 5/8" on the other to the quarter lip. Makes me kind of nervous being so close, but you must think that is enough?

 

[Black_Sheep]

I recently replaced the stock 8 3/4 rear on my 69 RR with a Strange 60. It must be a tad wider because I now have 9/16" clearance on one side and 5/8" on the other to the quarter lip. Makes me kind of nervous being so close, but you must think that is enough?

I have not had any issues so far...

 

[4mulas]

These were old real convo’s and were 8.5” rear with 4 7/8" BS. Fronts were 7" with 3 3/4” BS.

ran 275/60-15 MT drag radials On rear. Close to the rear spring but maybe had 3/4” max spacing away from it. It’s not the rim you’re worried about it’s the bulge of the sidewall once inflated. the tires would rub the upper inner wheel well when entering an alley etc, when the axle would go low in one side and higher on the other. There was more room to the outer lip if you wanted to run a 9 or 9.5" rim you probably could providing they had 5" or maybe 5 1/8" BS.

i probably wouldn’t use 10’s.

front ran 215/70-15 with no rub issue. Anything much wider or taller may have rubbed as the offset was slightly negative. If the fronts were negative offset (maybe like 4.25-4.5 BS) you run wider tires.