• Hello there guest and Welcome to The #1 Classic Mustang forum!
    To gain full access you must Register. Registration is free and it takes only a few moments to complete.
    Already a member? Login here then!

negative wedge kit

Fst Blk

Well-Known Member
If going with a negative wedge kit to drop the UCA 1 3/4 inches, will this help clear wider wheels? I ask because it looks like from all the research I have done that the wheels contact the balljoint. If you push it down another 3/4 inch will this help? I'm having a hard time finding 17x8 or 18x8 wheels in the style that I want. If I go with a 17x9 or 18x9 the search is easier.

Opinions???

Bill
 

Opentracker

Active Member
I've never been a fan of the wedge kit. When you install one, it spaces the ball joint away from the upper arm, making it harder to fit wheels with more backspacing on the car. Lowering the arm more than 1" does give more camber curve and that pulls the top of the tire inward with suspension compression so the tire may not hit the fender as easily. We cut, bend and weld up the upper arms to change the ball joint angle.

Looking at Nick's tire chart here -

http://www.dodgestang.com/cgi-bin/pro/e ... mbs;p=Tire and Wheel Charts 1965-1973/Tire and Wheel Chart

It looks like the 17 and 18 inch wheels can use 5" of backspacing on the front. The largest wheel we run on our cars is a 16" wheel and that has 4.5" of backspacing. I know that the larger wheels will clear the ball joint dome on the upper arm. I'm sure someone else on the forum will know more about the larger wheels than I do.
 

Fst Blk

Well-Known Member
Thanks John. I need to get some pieces done so I can mock it up and know for myself.


Bill
 

Fst Blk

Well-Known Member
Do you care to explain how you add negative wedge by cutting/welding the UCA's?

Bill
 

Opentracker

Active Member
I cut a wedge out of each side of the arm just behind the ball joint dome like this. Then I set it in my jig and bend the arm down so the gap is closed and weld it up. The ball joint ends up being just about flat with the top of the arm.



When your done, it looks like this. I weld a tab over the cut on the underside so it doesn't show and grind down the outside so it looks stock. This arm has a full brace on the underside as well but you can to the mod with just a tab welded over the cut.




Here's one with the ball joint angle change and the bracing on the outside.

 
Last edited by a moderator:

Opentracker

Active Member
Our drop is 1 1/2" but you could go 1 3/4" . There has been some testing done over the years about how far to drop the arm. We like the 1 1/2" drop. The bend of the arm is 18deg.
 
Top