how come 15x7 rallies don't fit my 67 GS?

[67NorCalGS]

The other day I got the opportunity to try out my buddies 15x7 rallies with 235 60 and they don't fit? There the Corvette style with a 4" backspace. What's the deal! Maybe it's because I didn't lower the car all the way but when it was up on jacks it didn't look like much room at all!

The original 14x6 rallies have about 4.5" backspace. I don't think a 1/2" of backspace would matter that much?

I did locate a set of modified Buick rallies 15x8 with 5" backspace. Some guy is selling because they did not fit his 65 very well. Do you think they will fit my 67? He wants 180 for the pair.

What backspace works best on a 67?

Thanks!

[Adam Whitman]

http://www.rallyamerica.com/32-36-68series.htm

They'll make them any backspace you want. My 64 used 5.5", and one of the 295-50's just barely rub on the inside against the wheelwell.

[lcac_man]

It will depend on the width of the wheel, lets take your 14x6 with 4.5bs for example :
A 14x6 wheel is actually about 7' wide to the edges of the flange where backspacing is measured from so to get a 6" wide wheel that centers the tire on the bolt flange you need 3.5" of b.s. not 3", yours have 4.5" so your tire actually sets 1" farther back in the wheel well (away from the fender)
Now on a 7" wide wheel (actually 8" to the flange edge) you would need 4" of b.s. just to center the tire.
So with the same width tire you would have 1" less clearance with the 7" x 4" b.s. combo than the 6"x4.5" combo.

[Jeff Martin]

Hi guys- Since were talking 67's, I need some advise on tire size.
Right now, my skylark is sitting on mickey mouse 195's and totally shot.:( I'm buying tires tomorrow and need help on size.I have 14" rallies, and was thinking of 225 or 235 70's. The 215's just don't seem to fill in the rear, so what do you suggest? Also , should I run the same size tires all around, or go bigger on the back?
Thanks for your help.:)

[lcac_man]

Jeff,
The availability of 14" tires is really drying up, you may want to consider biting the bullet and going to 15", there is a unending range of sizes and manufactures to choose from.
You can buy new 15" rallye wheels from Summit for less than $130 ea.

[67NorCalGS]

If I was going to buy new rims from summit what backspacing is the best for a 67?

Anybody?

[GS340PETE]

Going through something similar with my '67.

I asked my tire shop about your Corvette rally problem and he said it had to do with the offset and backspacing, which were different on 'vette style rally wheels.

I'm looking at putting 16x8 Edelbrock 454's on my car, they have an offset of '0' and backspacing of 4.5 inches, with 245-50's. The tire shop, and Global West, are telling me that these wheels will fit perfectly. I asked GW because I'm going to be getting their full suspension & 4-wheel disc brake setup and wanted to be SURE. Guess George's '67 and the other G-machines on here have gotten to me..................

This type of question/issue seems to come up an awful lot. Maybe somebody could do (or has done, for that matter) a web page or page through this site that talks about this and lists what will fit and won't for the different years of GS!

:beer

[gswes]

John,

With the original width rearend in your 67 CA GS you could run a 15x7 with 4 1/2" backspace. With this combo a 255/60/15 should be no problem. When I first got my 67 CA I put on Buick 15x7's with 4" backspace. I was using 255/50/15 but they would rub a liitle around corners. I then went to 235/60/15 & they fit fine.

The question I've got about the Chevy rallies. Were they the 15x7 Corvette (68 only) or are they the 15x7 rallies that they used on the later chevelles and montes? The early 15x7 Covette ralley looked just like a 15x8 from the outside.

With the original width rear you would have to get a 15x8 with about 5 1/2" backspace. That's assuming you want everything stuffed inside the quarter & not hanging out.

Wes

[67NorCalGS]

Wes,

I think they are mid 70's monte rallies 15x7. I don't know what's up but the 235-60-15 would'nt fit:confused: