Wheel Geometry help/advice

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IronRat

Well-known member
Joined
Nov 23, 2013
Messages
784
Location
ChicagoLand


My problem:

My '51 BelAir has the front clip from a 70ish Camero grafted on to it. The Disc brakes set the wheels out from the sides to an unacceptable point. On an unmolested '51 chevy the center point of the tire is approximately center in line with the headlight.

Not easy to tell but there's a lot of camber to make the current wheels work and one pot hole will allow the fender to rip the tires up.

The current wheels have a 3 1/2" back space. I'd like to stay some what period correct if I can. The best I can do with Steel wheels is 4.5" backspace. I found Salt Flat mags with 4.25" backspace. Powder coated with hub caps vs. the mags about the same price and either would look good. I'm afraid 3/4 -1" increased backspace won't be enough after a proper alinement is made.

I'm having a hard time visualizing the difference Disc/Drum when thinking were the mounted tire will sit inside the wheel well. Would switching to front drum brakes move my wheel into the wheel well?

Is Drum conversion + more wheel backspace my answer?

Thanks
 
Keep in mind, too much back space and you'll start rubbing the frame in turns. Whoever decided to put that sub under there needs a swift talking too.

THe only suggestion I have involves a lot of frame welding.... sorry.
 
Yep, wrong year of clip.
You won't gain anything going to drum brakes.
Best thing to do is order a pair of 6" wide wheels with a custom backspacing.
A 195-65 x 15 tire with the 4.25" wheels you found would work.
 
May be more trouble than its worth but people have shortened the A arms.

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look at some gm 15" wheels from the late 80' early 90's FWD type cars.

90's Monte Carlos had 15x6 wheels made to clear disk brakes, also on Grand Prix's, and other mid size FWD's
 
Keep in mind, too much back space and you'll start rubbing the frame in turns. Whoever decided to put that sub under there needs a swift talking too.

THe only suggestion I have involves a lot of frame welding.... sorry.

Yes and yes.

IF that subframe was going to be used it should have been narrowed prior to being installed. The only thing close to a way out now (short of starting over) is to narrow the A-arms themselves as in the picture SneakySnakes posted. It's really not that bad to do if you make careful cuts and are a competent welder.

Wheels that are heavy on the backspacing will look weird, not to mention out of proportion with the rears. No go on that...
 
I don't know as I haven't looked, but would there be tube A-arms available for the car? Or make a pair of tube A arms... just a passing thought...
 
You could shorten the A-arms, use narrow rims/tires and as much backspace as you can get. Maybe gasser kind of look. Smaller diameter tires would help limit frame rub if it becomes a problem. The only other real option besides re-doing the frame would be to alter the fenders, but on that body style, I can't really see anyway to make that not look like butt though.
 
Thanks everyone. I've been busy dealing with the weather.

Major surgery is not an option this year. I had a feeling that was the true answer to the problem

For those that weld, would it be faster/cheaper to just have Tube A-arms fabricated vs. shortening whats on the car now?

Current wheels are 15x7 w 3 1/2" back space.

I've found steel wheels 15X6 that have 4 1/8" back space vs. the 15x7 with 5 1/4. I think I'll buy a the 15x7 and try them on the front to check fit. They should work without issues on the rear.

In the rear the differential is from a 71 Grand Prix. I could use a little more back space there also. It's not as troubling as the front.
 
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