• When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.

Tire size for 70 roadrunner

cubbie3522

Member
Local time
3:35 PM
Joined
Nov 27, 2010
Messages
21
Reaction score
25
Location
New Castle, PA
I am in the process of purchasing 8" mag 500 wheels for the front and 10" for the rear, I will be putting these on my 1970 plymouth roadrunner. I was going with 245 r60 15 on front and 275 r60 15 on back. Saw a guy with 69 rr this weekend with same set up said it should work on my 70. The rear has a 5 1/2" backspace. Any idea if this will be an issue? I can still cancel the 10" if you guys think it won't fit.
 
That's the same size wheels and setup I've got on my '69 Sport Satellite, except I'm running 295/50/15's in the back. It's a tight fit with the 295's, but they work, so you should have no problems at all with the 275's.
 
If you are running 275's, I would go with an 8" wheel on the back - this setup is very common and fits great. 10" and 295's are very tight on Plymouths.
 
Tire width should match the rim width.... just because it fits doesn't mean its right....
 
Tire width should match the rim width.... just because it fits doesn't mean its right....

Soooooooo, you're trying to say I should be running 275's on my 10" wheels? 275mm is 10.83 inches. The guy I bought the car from had the same 295's on 8" wheels, that was definitely wrong, way too much bulge in the sidewall.
 
Soooooooo, you're trying to say I should be running 275's on my 10" wheels? 275mm is 10.83 inches. The guy I bought the car from had the same 295's on 8" wheels, that was definitely wrong, way too much bulge in the sidewall.

Yes sometimes the fattest rubber may look nice but is retarded in every other aspect... you need to account for body roll and steering clearance.... the fattys on the front can rub and cause issues with turning radius wear out parts cause hydroplaneing find a realistic combo I like 245 60 15 all the way around on 8" mag 500s 4 1/2" off set... kick it around a while it's something to ponder
 
Yes sometimes the fattest rubber may look nice but is retarded in every other aspect... you need to account for body roll and steering clearance.... the fattys on the front can rub and cause issues with turning radius wear out parts cause hydroplaneing find a realistic combo I like 245 60 15 all the way around on 8" mag 500s 4 1/2" off set... kick it around a while it's something to ponder

Who said anything about running tires larger than 245 in the front? As I stated, I'm running the same wheel and tire setup the OP asked about, just with 295's in the back instead of 275's. Your point about the size of the tire matching the size of the wheel is interesting, however, I'm very happy with the wheel and tire setup on my Plymouth. It handles great with the hotchkis suspension and wheel/tire combo I'm running. The only problem I've ever had was some tire rub on the outside lip of the wheel well where the quarter rolls in and that was because of the replacement quarter skin someone had put on before I had it where that lip was sticking out further into the wheel well than it should have. Easy fix for the hot rod shop around the corner from my work. To each their own I guess.
 
i got 18x9.5 with 275 out back with 5.75 backspacing...i got plenty of room. hope this helps ya out
 

Attachments

  • IMG_20140408_181920_009.jpg
    IMG_20140408_181920_009.jpg
    38.4 KB · Views: 495
  • ResizedImage_1397354495495.jpg
    ResizedImage_1397354495495.jpg
    52.3 KB · Views: 464
Thank you guys, I got the 8" today think I'll wait on the tens to get here and try it. Worst case I'll have a set of tens to sell!! Lol
 
Thank you guys, I got the 8" today think I'll wait on the tens to get here and try it. Worst case I'll have a set of tens to sell!! Lol

if you got the right backspacing the 10s should still work. my opinion i would go 285. 295 is getting tight. jmo. hope it works out.
 
When the rim with matches the tread with it helps to keep the tire from ballooning when it is at high speed.... use the 10's or you will wear the centers out unless you do a lot of donuts....
 
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.
IMG_0678.jpg
 
Fit or not the tread and rim with must be the same.... Or close for the tire to ride properly.... I would not run anything larger than a 245 on 8" 235 is ideal... if a narrow rim to tread with is used it will cause the tire to crown if a wider rim than the tread with it will cause the tire to cave and wear on the out side... just because someone can mount up tires and they fit doesn't mean anything.... the with of the tire should closely match the with of the rim...
 
Auto Transport Service
Back
Top