15x10 Rallies on a '77?

[Dimitri13]

I have a '77, and the fenders/arches are flared out a bit. That makes it look awkward with the stock 15x7 (or 8, I'm not sure, it's not in my possession right now). There's a set of Corvette 15x10 rally wheels for sale locally, and I'd like to know if they'd clear the frame/suspension with a reasonably sized tire.

[Dimitri13]

Well, seems like there's not much of an answer to this (I searched before and after posting this), so I guess I'll ask a more appropriate question:

Anyone have a how-to on how to measure everything in there so I know what kind of clearances I'll have?

[LOCKJAW]

Keep in mind a tire for a 10" wheel will have a section width of at least 13" ! I don't think they will work without tubbing. You also need to calculate backset of the wheels. Over my paygrade..

[Dimitri13]

13"? That'd be like a 330.

I'd be using a 275 or 285.. Unless I don't quite understand how tires work

[LOCKJAW]

Jamie, "section" width is the widest area (sidewall") and is always wider then the tread
I run 255r70 15's in the rear . The widest area is 10.5 inches on a 8" wheel. I have to disconnect bottom shock mounts and drop axle to remove wheel/tire. Your area might be bigger . Ten inch wheels will be a squeeze at best.
Hopefully another 77 owner will have a definitive answer for you.

[Dimitri13]

Thanks James.

I guess the only real way to find out is to get under there and do some measurements. I was just hoping I could get a definitive answer before I took possession of my El Camino (will be picking it up tomorrow, so I can measure then), so I could order wheels/tires early.

[LOCKJAW]

You might contact HKDUP87 (Robert) about this. He just swapped out some big wheels and can probably help. He is very detail oriented. There can't be very difference 77/87 models as far as fenderwell area.

[Dimitri13]

From what I read the differences are noticeable. I'm on the board of directors of a corvette club here, I'll probably see if one of our members is willing to loan me one of their wheels for test fitment :P

[ND Harman]

Hi Jaymie,

I don't know about the width of the rim but I know you should be able to fit 295/50R15's on the back without too much issue (BFG's that size can go from an 8" rim to an 11" according to summit). There is a link to a post I made when I switched my rims and tires in 2011. I mistakenly said 295/60R15 but they would probably fit as well. I am looking to go up to a 28" tall tire with my next set. My rims are 15x8" with a back spacing of 4". Up front I seem to have a good amount of space lock to lock but I don't know about another inch. Doing a test fit would be a good idea if you are able. I think you would have some rim hanging out past the fender lip if you went with an even 5" backspace.

http://www.elcaminocentral.com/showthread.php?t=42353

[Dimitri13]

Hey Harman, that's for the great info! I just got my Elky here, and they're 255s. I have 3" of clearance to the fender, but I didn't check the clearance to the frame.

It's a shame they only seem to sell 15x10s with 5 or 5.5" backspacing.

[Maxfield]

You can put 15x10 wheels on front with a 4 1/2'' back spacing,but you will need to put 245/60r15 or smaller to not rub when turning.You can fit 275/60r15 That our 28'' tall and a tread of 9 in wide but you will need to raise the front end up 3'' over stock. The offset of the wheel is the distance from the back side of the mounting flange to where the bead of the tire is.The offset of 4 1/2 is truley 5'' to the very edge of the back side..On the rear you can put as wide as 12'' but the back spacing will need to at min 5 1/2 and no more than 6 1/2 .But to get back to your question yes 15x10 wheels off a vett will work ,front and rear the tire size on rear can be almost as big as you want, but on the front 245/60r 15 is as big as you can go at stock height.IF anyone has questions about wheels and tires iv been in the industry for 35 years and will be more than happy to help in any way i can.

[Dimitri13]

Thanks Maxfield.

I'll likely be keeping the 15x8s on the front.

The clearance from the 255 tire on an 8" (4" backspace) wheel to the frame in the rear was over 2". I'll be good with the 275 on the 10" wheel (5" backspace). I might even have to use a spacer to get the tire closer to the fender just to fill it out.

[tv5150]

Thanks to ALL for the great info on fitting these 15 X 10 on a 4th Gen
I pulled the triggger on a pair of the Wheel Vintiques from Summit
with the 5.5 inch back spacing today..I'll try to get some pics posted
when I get them and trial fit them without tires...
More to to follow later...TV