14x7 to 15x7 Rally Wheel Swap...

[oneZ11]

I've got a '69 with original 14x7 Rally's and am looking to put a set 15x7's on. Do I have to find '68-69 wheels, or will the early 70s "FW" code wheels work the same?

My research shows that the original 14x7's have a 4" backspace. 15x7's?

[tom]

Mine had FW wheels when I bought it. Still needs work, so can't comment on fit or clearance issues. I know the owner for several years before me did not add them.

[oneZ11]

Yours were probably added later. "FW" code doesn't show up on 1969 code chart for Camaro Rally's, so that's encouraging. Are yours 15x7s?

(You can research this site for wheels codes.)

[69Z28-RS]

I believe FW was a Monte Carlo code, and many of them have been used on Camaro's over the years... might be a fractional inch difference in offset from the YH?   I can measure the offset on one of my YH's tonight if you need (tired is dismounted so should be easy)..

Gary

[oneZ11]

If not too much trouble, that would be great. I think it's 4.25" on the 15x7 wheel, but I could be wrong.

[mcharter]

Hope this is not off topic but I had done some research a while back on wheels.  I think I found that 15x7 YH wheels were identical to FW wheels.  I thought they even had the same GM part number 3997899-D.  Does anyone know if this is correct?  Thanks

[oneZ11]

YH code would be Z28 wheels – would love to have an original set of those! Sorry, can't answer the part number question. I'm mostly interested in proper fit, so there's no tire rubbing. Also, want the 15" rim, so I can run the deeper style trim ring.

[oneZ11]

Found this on another blog, RE: backspacing...

FW  15X7  Backspacing 4 1/4  71-up most any GM

YJ  14X7  Backspacing 4 3/8   69 Camero/ Chevy II L72- ZL1, 70 Nova

[Stingr69]

The Monte Carlo FW rims are fine.  Those are what I have been running for many years.  Same dimensions as the Z/28 YH code wheels.  Only slight visual differences under very close inspection. 

The biggest tire that you can run on all 4 corners with those is a P245-60-15 but that size will require a very slight bend in the inside flange of the front fender extension. You can just about do the mod with your hand and it is easy to reverse so it is no big deal.  A P235-60-15 might be a better look to some eyes as it is slightly less aggressive.

-Mark.

[69Z28-RS]

I have an FW wheel unmounted, and a YH wheel unmounted in my garage.  I measured the back spacing tonight from those wheels tonight:

YH       4-1/4" backspace
FW       4-3/8" backspace

I only measured one wheel each, but I have others of both codes if there's still question...

Gary

[Kelley W King]

FW,s are everywhere. They work on camaros fine. I have 2 with them now.

[oneZ11]

Thanks for the info guys - and thanks for measuring "69Z28-RS."

"Stingr69", thanks, I will probably run a 225 or 235 but no larger. It's weird how tire diameters run. A 225/70 R14 is a larger diameter than a 235/60 R15 !

[69Z28-RS]

You should be able to calculate the tire Dia (height) using the formula; to keep your effective gear ratio and speedo cal the same, you should try to keep your tire height the same or very similar.

Height of 225/70R14 = Rim (14*25.4) +  2* tire section (0.7*225)= 355.6 + 315= 670.6 mm =  26.4" Dia
Height of 235/60R15 = (Rim (15*25.4) + 2* tire section (0.6*235) = 381 + 282 = 663 mm = 26.1 In Dia

Is this close to what your tire book said?

Gary

[oneZ11]

Actually, no book, I'm using Tire Rack.com. Look up any tire, and click "specs" in the table below. They provide all dimensions of the tire including diameter. Very nice feature...