Known correct information please !!

[Polpette]

I have a 66 Coronet with a stock 8-3/4 diff. I want to add wider tires on the rear and am looking for a straight answer as to what size wheel, tire and backspacing. I have read several threads that indicate a 15x8 with 4.5" back space is the way to go with utilizing 275/60R15 tires. I have the Magnum 500s and plan on sticking with them. Is this a good combo or should I be looking for something different? Also I am going to keep Redlines as the car has them now. I appreciate all the help you are able to provide !! Thank you in advance !! P.S. NO grief about the Barrett Jackson logo The car sold at their auction and I bought it from that person!!

 

[Jerry Hall]

My opinion is you will never get that combo of wheel and tires to work on your 66 Coronet. I have that combo on a 68 R/T and it's fine. I can't even jack my 67 R/T up enough to put that tire and wheel on it. I have 235/70 15's on 15X7 magnums on my 67 R/T and they will scrub slightly under certain circumstances.

 

[440 4 speed]

My opinion is you will never get that combo of wheel and tires to work on your 66 Coronet. I have that combo on a 68 R/T and it's fine. I can't even jack my 67 R/T up enough to put that tire and wheel on it. I have 235/70 15's on 15X7 magnums on my 67 R/T and they will scrub slightly under certain circumstances. View attachment 1977629

If you don’t put a lot of beer in the trunk, that will stop some of the scrubbing. My very humble opinion !

 

[Jerry Hall]

If you don’t put a lot of beer in the trunk, that will stop some of the scrubbing. My very humble opinion !

I said certain conditions.

 

[Sam69sat]

I have a 66 Coronet with a stock 8-3/4 diff. I want to add wider tires on the rear and am looking for a straight answer as to what size wheel, tire and backspacing. I have read several threads that indicate a 15x8 with 4.5" back space is the way to go with utilizing 275/60R15 tires. I have the Magnum 500s and plan on sticking with them. Is this a good combo or should I be looking for something different? Also I am going to keep Redlines as the car has them now. I appreciate all the help you are able to provide !! Thank you in advance !! P.S. NO grief about the Barrett Jackson logo The car sold at their auction and I bought it from that person!!View attachment 1977625

Nice looking coronet! What is the current rim and tire size?

 

[Aron Gleason]

I have super stock leaf springs on my 67 coronet with 15x8 cragar wheels and 5 inch backspace. 275/60/15 drag radials fit with no problems

 

[Polpette]

Nice looking coronet! What is the current rim and tire size?

235/60R15 - Front and Rear

 

[Polpette]

235/60R15 - Front and Rear

And thank you for the compliment!!

 

[R413]

Do you want them to rub sometimes, or never rub?

15x7 and 255/60's is much more forgiving

 

[Dave6T4]

I used to have 255/70R15 on 15 x 8 custom police wheels that I made to fit exactly in the middle of the confines of the wheelhouse. Unfortunately, I do not recall the backspace. While I had good clearance around the tire statically, once I started driving the car, and it was free to move around on its suspension, I found the sidewalls were being marked. I installed a frame-hung rear sway bar, similar to the ones used on some Challengers and 'Cudas and this solved that problem. With 60 series tires being wider than 70 series, these would present more of a problem. The '66-'67 B-body wheelwells are the most restrictive of our musclecars. I believe Firm Feel sells a version of the sway bar.
I now run 235/70R15 Redlines on the rear of my '67 R/T, and 215/70R15 on the front. I found that 225/70 on the front would rub on the front framerail on full turns.

 

[33 IMP]

If you are gonna keep redlines, you better find who makes the size you want. I've never seen 275 60 redlines
If you like the wheels you have, and they are 15x7, I'd simply move to 255 60s......or, 255 70s if they aren't too tall.
Known correct? Then do your own measuring on your car. (They do vary).