Will It fit

[Virg464]

Looking at picking up a set rear tires so I can move the car around, and put it on the road for a little testing/shake down, 66 Coronet with 10" slicks on it right now. I live in a rural area and have to travel about a mile to get to the black-top. So, I'm eye balling a set of 255/60R15 to put on a set of steel wheels, pretty sure the tires will fit but my question is backspacing on the wheels. From what I've found/read so far 4.5" back space would work just fine, my steelies have 4.25" back space. Think that will cause an issue with the edge of the wheel well opening?

 

[33 IMP]

I have 255-70x15s on an 8 inch 4" bs steelie. (ramcharger wheel, I think.) On a 62.
The 66-67 wheelwells are the smallest on b-bodies, less room than my 62.
I'd consider going down a size or so, maybe a 235 or 245.
Simple question: what's the backspace of the wheels the slicks are on? (They must be "RIGHT" , to get a ten inch slick on a 66-67.)

 

[GTX JOHN]

Agreed.... The 66/67 are a real pain.
I do not know how you got a 10 inch slick on
it unless they are short or it is modified.
For just driving around = I would run a 70
series if it is not going to be raced on those tires.

A quarter inch is not much difference in spacing.

 

[R413]

How wide is the wheel in question? 8" will be a problem with 4.25 backspace, a 7" should fit.

The 255/60 will fit fine with the correct offset.

What was modified to put a 10" slick on there. Or is the back bumper 3 feet high?

 

[Virg464]

OK, my bad just went out to confirm what I have. I was wrong! 28.0/9.0/15 slicks. So, 255/60R15's are out, I'll go with 245's.

 

[Virg464]

How wide is the wheel in question? 8" will be a problem with 4.25 backspace, a 7" should fit.

The 255/60 will fit fine with the correct offset.

What was modified to put a 10" slick on there. Or is the back bumper 3 feet high?

the wheels are 8" wide, but only have 4.25" back space.

 

[guy gadbois]

225/60 x 15 on a 7 inch wheel have about a quarter inch clearance on my 67...

 

[R413]

Wrong wheel for the car. Up to a 275/60-15 will fit with the right wheel

 

[Virg464]

Wrong wheel for the car. Up to a 275/60-15 will fit with the right wheel

OK then, 255's are still on the table, I'll just have to find the right back space to get them in there.

 

[BSB67]

Just did this a few days ago. 255-60-15 on a 7” rim with 4.25” back spacing. Works fine.

This is with standard replacement rear springs - no lift.

 

[Virg464]

Just did this a few days ago. 255-60-15 on a 7” rim with 4.25” back spacing. Works fine.

This is with standard replacement rear springs - no lift.

View attachment 1839488

View attachment 1839489

View attachment 1839490

Awesome! Thanks for the pics.

 

[R413]

@BSB67 has the recipe right there.
And that blue is a great color on these cars too!

 

[33 IMP]

....and your 8" wheel with 4.25 backspace moves everything in bsb's example a full inch closer to the fender.
Does it look like there's an extra inch of room there?

 

[BSB67]

....and your 8" wheel with 4.25 backspace moves everything in bsb's example a full inch closer to the fender.
Does it look like there's an extra inch of room there?

Exactly!

And the tire cross section gets a 1/2” wider on an 8” rim. So it could be more than an inch.

The inner fender on my X runs parallel to the contour of the tire side wall. I don’t have much more than 1/2” clearance. I worked the suspense pretty hard with two of us in the car and nothing rubbed. 4 people in the car, maybe it would.

My tires are the MT ET Street Rs. They might be just a little bigger than some other P255-60s.

 

[Virg464]

....and your 8" wheel with 4.25 backspace moves everything in bsb's example a full inch closer to the fender.
Does it look like there's an extra inch of room there?

OK, correct me if I'm wrong, this may be a "caveman" way of evaluating it. Theoretically, I should be able to take the slicks off, with the rear axle on jack stands at normal ride height, use a framing square laid against the brake drum, and measure out to the inner edge of the wheel well opening? There by giving me the max distance I have from (wheel to drum) mounting surface to the wheel well edge? This will allow me to calculate the needed back space to get that 255 tire in there?

 

[33 IMP]

OK, correct me if I'm wrong, this may be a "caveman" way of evaluating it. Theoretically, I should be able to take the slicks off, with the rear axle on jack stands at normal ride height, use a framing square laid against the brake drum, and measure out to the inner edge of the wheel well opening? There by giving me the max distance I have from (wheel to drum) mounting surface to the wheel well edge? This will allow me to calculate the needed back space to get that 255 tire in there?

Your 9" slick is probably bigger than a 255. Pull the slick off, measure the backspace , and duplicate it on the new rims.



Or just pull the slicks off and put your 255s on.
Edit: 255/60x15s are about 3/4" shorter, and slightly narrower (in tread width) than your 9x28 slicks.

 

[Virg464]

Set two squares on the floor, one one each side of the slick to measure the cross section width including the sidewalls - close to 11" or 279 mm, think I'll be OK with the 255's. Going to pull one of the slicks off and measure the B/S, it's got more space on inside than outside, so I'll order the wheels with the B/S accordingly. Thanks guys!

 

[33 IMP]

Set two squares on the floor, one one each side of the slick to measure the cross section width including the sidewalls - close to 11" or 279 mm, think I'll be OK with the 255's. Going to pull one of the slicks off and measure the B/S, it's got more space on inside than outside, so I'll order the wheels with the B/S accordingly. Thanks guys!

Do you know the width of the wheels the slicks are on?
(It might say what size on the backside of the wheel.)

 

[Virg464]

Do you know the width of the wheels the slicks are on?
(It might say what size on the backside of the wheel.)

I didn't think to look for the info on the wheel itself. As close as I could measure (roughly) 8", but that's sticking a tape through an opening in the wheel, eyeballing it, etc. I will for sure check for the info tomorrow though.

 

[33 IMP]

I didn't think to look for the info on the wheel itself. As close as I could measure (roughly) 8", but that's sticking a tape through an opening in the wheel, eyeballing it, etc. I will for sure check for the info tomorrow though.

You can confirm wheel width with a straightedge and a tape measure.
Lay the wheel flat, straightedge across tire cross section, measure to the ground thru center hole. Hypothetically call that 11 inches. Then measure to from straightedge to edge of rim. Call that one inch. Multiply by two (front and back side) leaves 9". With an aluminum rim, beads are about 1/2", so.... an 8" rim. Steel? Probably an 8 1/2 rim.
Your numbers will vary.
And the info might be on the back side, you won't have to do anything but measure bs.
Edit I just had to change out some aluminum rims on my car trailer.
The inside of the wheel had the brand, tire diameter, wheel width, and load rating cast into the wheel... and they are at least thirty years old.