Wheel advice

[bricud]

I've been getting my 1969 Barracuda road ready and am looking for some wheel advice. I have disc brake conversions on both front and rear and the front has the 5 x 4 bolt pattern but in the process of changing the rear end I put in some hd axles that have the 5 x 4.5 bolt pattern. I've been looking at wheel options (which are very limited) and am considering ordering the Crager Series 08/61 S/S. That way I can put 15" wheels all around. I am limited to the 15 x 7" up front (smallest with 5 x 4 bolt pattern). This has a 4.1" rear spacing. Is that a problem? Otherwise I would have to go with the 14" wheel up front to get a narrower wheel with 3.4" rear spacing.

On the back, I can put in a 15 x 10 with a 5 x 4.5" bolt pattern. This wheel has a 4.3" offset. Probably put a 255/60 or 265/60 on the rear if they will fit in the wheel wells. Otherwise I can put in a 15 x 8 that has a 4.3" offset but limits my tire width to 245/60 max. Any advice will be helpful.

Brian

 

[33IMP]

Most of the extra width of the 15x7 in the front is to the inside. It should fit with a moderate sized tire. A 14x6 should fit easier, but I would avoid 14"tires if possible.
I seriously doubt a 15x10 will fit with that backspace. It would need more like 5.5 " bs.

The 15x8 will fit much better. Once you have the wheels, tire size can be determined.
If you have clearance, a 255 on an 8"rim is fine.
Oh, and one more important thing: you've gotta get your terms correct. Backspace and offset are ENTIRELY DIFFERENT measurements. Three or four inches of offset probably won't fit anything! (If that 15x7 has 4.1" of backspace, the offset will be somewhere around zero, or a couple millimeters either way.)
Also, no such thing as a 265/60x15. only 255 or 275. 275 is even okay on an 8"rim...... IF you have the room, and IF the wheel backspace is exactly right.

 

[bricud]

Thanks for the information. So let me make sure I understand on the offset/backspace. I'm still not sure I understand. Thanks for your patience. In the Crager spec sheet, the 15 x 7 rims have specs that say "4.1" rear spacing, 2.8" center bore". On the 15 x 8 rims, it says "4.3" rear spacing, 3.6" center bore". I wasn't sure what their terms mean. Their part numbers are 1526461402B on the 15 x 7 and 1526581402b on the 15 x 8. Thanks in advance for your help.

Brian

 

[33IMP]

Pretty easy, really. (At least backspace)
Rear space and backspace is the same thing. It's the measurement from the inside edge of the wheel to the mounting face. Almost always in inches.
(Center bore is the size of the center hole for axle flange or disc hub size).
Offset is how much the mounting surface is off center in the rim. Almost always in millimeters.
First, know that a rim is measured between the beads, so a aluminum rim (which most cragars are NOT) that's "eight" inches is really about nine inches overall. So, an eight inch rim with 4.5" backspace will be ZERO offset (even distance to center, front and back). If that same rim has 3.5" backspace, it would have (roughly) 25mm offset.
Then there is plus or minus offset. I can never remember which is which, so I don't try.
Backspace and rim width can tell me about 95% of the time what will fit, and can be measured with a straightedge and a tape measure.
Offset has to be calculated, CANT be measured, and you need to know the wheel width and backspace as first step. Why bother?
You can Google wheel offset and figure out which direction (mostly in or mostly out ) is which.

 

[bricud]

Thanks. That helps a lot. So I think this means that the Cragar 8" rims with 4.3" of rear spacing is likely a 0 offset assuming they are really about 8.6" wide. You mentioned most Cragars are different than most aluminum rims. So is an 8" rim really closer to double of the back spacing they are specifying, meaning they are really about 8.6". Also, if I go with the 7" rims up front and the 8" rims with the specs listed above, they should fit without interference. Just wanted to make sure before ordering.

 

[Righty]

I have SBP hubs front and back so I went with the Cragars 15x7 front and 15x8 rear. I found 215/60 fits comfortably at the front and probably could go to a 225/60 even maybe a 235/60. At the rear I went 235/60, however it does depend on the tyre make because the cheap Vitour Galaxies I’m running are wider than the given section width at about 255 wide, there is clearance to add another 10mm to that either side, so in theory I think a 275/60 would work if it is true to that dimension.

 

[bricud]

Thanks for your feedback. I wanted to go as wide as I can in the in back within reason. I was thinking I would likely go with the 255's on the back.

 

[matthon]

Barracudas have less fender lip space in the front than other a-bodies.
The wrong offset or tire size, and the tire will rub the front bottom corner of the fender lip.

See this thread, my post #29 details my before and after.

I went from Cragar14x6 wheels, backspace at 3.75 and the tire is a 215 70 14.

To 15x6 steelies, backspace 3.75, offset +6 mm, 215 65 15.

Tires are nearly identical and come as close as possible without rubbing during all driving conditions.

What size tire using 15x6 wheel?

And I have 255/60 on 15x8 on the rear.

 

[33IMP]

Thanks. That helps a lot. So I think this means that the Cragar 8" rims with 4.3" of rear spacing is likely a 0 offset assuming they are really about 8.6" wide. You mentioned most Cragars are different than most aluminum rims. So is an 8" rim really closer to double of the back spacing they are specifying, meaning they are really about 8.6". Also, if I go with the 7" rims up front and the 8" rims with the specs listed above, they should fit without interference. Just wanted to make sure before ordering.

Cragar ss are a chrome plated steel barrel, with a chrome plated aluminum hub. Since a steel hoop doesn't need as thick a bead as an aluminum wheel an 8.6 guess for overall width is a good one. So yep, I think a 15x8 steel wheel with a 4.3 backspace is probably zero offset.