More drag radial questions

[BandBSTANGS 15]

On a 1970 coupe what size drag radial would fit the best?

I would like to use a 8 inch magnum 500.

235/60 15 or 255/60 15 ?

Car only has a 3:50 gear, so I'm afraid that a 275/60 15 would be too tall and that a 8 inch rim would be too narrow and bulge the sidewalls.

What offset do the 8 inch magnums have?

The 245/60 15 T/A radials on the car are like ice skating!

[mustangmike6996 34]

If the 245s are too narrow then you will hate the 235s.

 

Heres how they are broken down

 

275/60/15

 

275= the section width of the tread represented in millimeters (275 mm)

60= aspect ratio. A percent of the section width. So 60% of 275mm (165mm) sidewall

15= diameter for the rim opening

 

Like stated above, if you don't like the 245s due to being too narrow you will hate the 235s AND the 235s will have a shorter sidewall (due to a narrower section width at the same 60%)

 

Your best bet, since you have some wheels and tires on the car are to measure how much clearance there is from the sidewall to the inside wheel housing and then to the outside wheel housing (with the vehicle sitting on the ground, not jacked up) This will let you get a feel for how far the offset is (how far the wheel barrel sits in or out on the face, the face is what you would see as the spokes)

 

For example, if you have 1" from the tire to the quarter panel and about 2-3 inches from the wheel housing to the back of the tire, you can keep the same offset wheel, get a wider wheel (and have deeper backspacing due to the added width) then put a wider tire on the car.

 

Some things you want to consider

 

Go on EACH manufactures website for specific data because tires are like shoes, sizes are guidelines and no brand is exact to the next

 

Consider what you want your final drive ratio to be, this can be calculated with trans top gear ratio, rear axle ratio and overall tire circumference. That will give you your speed. So a taller (larger circumference) tire will give you a numerically lower gear ratio so to speak. It will be like a highway gear.

 

A shorter tire (less circumference) will give you a higher numerical gear effect. Spin the tires faster (like going from 3.50s to 4.10s)

 

275 might fit in the wheel opening but might have a large sidewall. You need to figure out quite a few things (all at the same time) to get the best of all situations. Yea some big meats in the back look great but kill performance. Some well calculated tires perform great but look undesirable. Its all about balance.

 

Are you planning on getting different rear rims? If curious why you ask about offset

 

A 255 60 would probably look and perform the best but there is still something that is left on the table in my opinion. I like fat rear tires but I don't like fat rear tires, a ton of sidewall to the point the car looks like a funny car or mad max. If that is what you want, the 275 60 is what you would want to look at

 

The difference in the 255/60 to the 275/60 is 153mm sidewall or a 165mm sidewall which is 1/2" then double that (sidewall on each side of the rim) you are looking at almost 1 inch of sidewall height total between the two tires.

Edited December 5, 2014 by mustangmike6996

[barnett468 418]

.

whats wrong with a 245 x 60 drag radial? . . it will fit an 8" rim.

.

Edited December 5, 2014 by barnett468

[sportsroof69 13]

If the 245s are too narrow then you will hate the 235s.

 

Heres how they are broken down

 

275/60/15

 

275= the section width of the tread represented in millimeters (275 mm)

60= aspect ratio. A percent of the section width. So 60% of 275mm (165mm) sidewall

15= diameter for the rim opening

 

Like stated above, if you don't like the 245s due to being too narrow you will hate the 235s AND the 235s will have a shorter sidewall (due to a narrower section width at the same 60%)

 

Your best bet, since you have some wheels and tires on the car are to measure how much clearance there is from the sidewall to the inside wheel housing and then to the outside wheel housing (with the vehicle sitting on the ground, not jacked up) This will let you get a feel for how far the offset is (how far the wheel barrel sits in or out on the face, the face is what you would see as the spokes)

 

For example, if you have 1" from the tire to the quarter panel and about 2-3 inches from the wheel housing to the back of the tire, you can keep the same offset wheel, get a wider wheel (and have deeper backspacing due to the added width) then put a wider tire on the car.

 

Some things you want to consider

 

Go on EACH manufactures website for specific data because tires are like shoes, sizes are guidelines and no brand is exact to the next

 

Consider what you want your final drive ratio to be, this can be calculated with trans top gear ratio, rear axle ratio and overall tire circumference. That will give you your speed. So a taller (larger circumference) tire will give you a numerically lower gear ratio so to speak. It will be like a highway gear.

 

A shorter tire (less circumference) will give you a higher numerical gear effect. Spin the tires faster (like going from 3.50s to 4.10s)

 

275 might fit in the wheel opening but might have a large sidewall. You need to figure out quite a few things (all at the same time) to get the best of all situations. Yea some big meats in the back look great but kill performance. Some well calculated tires perform great but look undesirable. Its all about balance.

 

Are you planning on getting different rear rims? If curious why you ask about offset

 

A 255 60 would probably look and perform the best but there is still something that is left on the table in my opinion. I like fat rear tires but I don't like fat rear tires, a ton of sidewall to the point the car looks like a funny car or mad max. If that is what you want, the 275 60 is what you would want to look at

 

The difference in the 255/60 to the 275/60 is 153mm sidewall or a 165mm sidewall which is 1/2" then double that (sidewall on each side of the rim) you are looking at almost 1 inch of sidewall height total between the two tires.

 

He didn't say he didn't like the 245s because they were too narrow. He said he didn't like them because it's like ice skating. A 235 DR will be an unmeasurable amount better traction wise than the 245 BFG radial T/A he mentioned. Size doesn't equal traction

[sportsroof69 13]

On a 1970 coupe what size drag radial would fit the best?

I would like to use a 8 inch magnum 500.

235/60 15 or 255/60 15 ?

Car only has a 3:50 gear, so I'm afraid that a 275/60 15 would be too tall and that a 8 inch rim would be too narrow and bulge the sidewalls.

What offset do the 8 inch magnums have?

The 245/60 15 T/A radials on the car are like ice skating!

 

Back spacing can vary depending on what they ordered. I use an 8" wheel with 4.5" back spacing. I run a 28X10.5 slick and a 275/60 drag radial. They both work well.

[BandBSTANGS 15]

In reading the responses its evident that my initial post wasn't very coherent reading it.

My car has 15x7 magnum 500's on it now and was looking to keep the same look.

I wanted to be able to swap back and forth drag radial to street tire due to wear issue with drag radials.

I was at the strip last week end and one of my friends had 275/60 15 drag radials on his s-10 and I took a quick measurement and it appeared that tire had approx. 9.5 inch tread patch and sidewalls appear to bulge out to almost 11 inches.

If my memory serves me correctly (ooohh look a kitty!) the 8 inch magnum is more of a deep dish look. The addl inch is on outside of rim.

That is why I asked about the 8 inch magnum offset, I'm afraid if the offset is to the outside and drag radial have that much sidewall bulge that tire may get into outer fender well of 1/4.

I have 235/60 15 t/a radials on frt of my car and 245/60 15 0n rear right now. (non-hooking pos, but they look good.)

That is why I'm thinking 235 or 255 drag radial, plus I don't want to kill what gear I've got with 275 height (I think?)

My Cleveland spins 6500 with ease so I want take tire height into consideration and not kill my 3:50 gear with tire height.

[demon 13]

The Nittos work very nice on lower HP cars like mine approx 425HP. They last a lot longer than other DR, most are getting 10to 20K. they hold pressure great 28psi since spring! 276/60/15's

[BuckeyeDemon 211]

If my memory serves me correctly (ooohh look a kitty!) the 8 inch magnum is more of a deep dish look. The addl inch is on outside of rim.

That is why I asked about the 8 inch magnum offset, I'm afraid if the offset is to the outside and drag radial have that much sidewall bulge that tire may get into outer fender well of 1/4.

 

Specialty Wheel did a custom offset on my 15x8 magnum for something like $20 extra and about 2-3 weeks several years ago.

[sportsroof69 13]

If you're going to swap them and they primarily be a track wheel, the M/T ET Street pro radial is the only way to go.

[barnett468 418]

you didnt answer my question so i dont know what else to suggest.

[BandBSTANGS 15]

Nothing wrong with 245/60 radial.

Do you have a brand suggestion in this size?

[barnett468 418]

Nothing wrong with 245/60 radial.

Do you have a brand suggestion in this size?

 

sure . . the ones below are pretty much your options in the size range you want.

 

these are the only mt street tires close to a 245 x 60 -15

http://www.mickeythompsontires.com/strip.php?item=ETStreet

 

drag only in close to 235 x 60 x 15 size . . 24.5 tall x full 8†wide flat tread - 15

http://www.mickeythompsontires.com/strip.php?item=ETDrag

 

24.5 x 8 – 15 for 8†rim

http://www.mickeythompsontires.com/strip.php?item=ETDragSportCompact

 

hoosier 26 x 10 – 15 slicks for 9†rim or scroill down to quick time pro dot and quick time dot

https://www.hoosiertire.com/pdfs/specdrag.pdf

.

[mustangmike6996 34]

He didn't say he didn't like the 245s because they were too narrow. He said he didn't like them because it's like ice skating. A 235 DR will be an unmeasurable amount better traction wise than the 245 BFG radial T/A he mentioned. Size doesn't equal traction

 

 

AHHH I read it as he didn't like them because the look like ice skates.....

 

oops