What is the wedge angle on negative wedge kits?

I made a set for my '70 on a bridgeport out of 6061 aluminum, and I made them 18 degrees. I don't know what Pro motorsports does. I did a 2 inch UCA drop and I figured that 18 degrees covered that approximate angle change for the '70 UCA length. It depends on how much you move the UCA mounting point how much angle you want. Tangent(angle) =(opposite/adjacent)=UCA mounting point drop/UCA length. I hope that is helpful. It's not mathematically exact, but close enough to prevent the ball joint from binding by my estimation. You should spend some time and thought to convince yourself as to what will work for you.

I really wanted to do the Opentracker style modification to my control arms - that is, cut a wedge from the UCAs, bend and reweld them with reinforcements to the proper angle. At the time I didn't spend enough time on figuring out how to do that with my '70 UCAs. It has a few advantages of keeping the UCA weight down and fewer parts. IMO you should consider doing this rather than making a wedge to bolt in.
 
I made a set for my '70 on a bridgeport out of 6061 aluminum, and I made them 18 degrees. I don't know what Pro motorsports does. I did a 2 inch UCA drop and I figured that 18 degrees covered that approximate angle change for the '70 UCA length. It depends on how much you move the UCA mounting point how much angle you want....

I really wanted to do the Opentracker style modification to my control arms - that is, cut a wedge from the UCAs, bend and reweld them with reinforcements to the proper angle......

That's what I'm wrestling with right now. If I'm going to do a permanent mod to the shock towers, I don't want to regret not going far enough. I don't want to go the easy way with just 1" and no wedges if there is more gain to had with 1.75 or 2".

I'd get another set of UCAs and try the Opentracker mod, but I don't trust my welding yet on something structural like that. The car is going to be lowered, so I have to do something.
 
I made a set of wedges, even made angled washers so the bolts wouldn't bend when I tightened the ball joint. You need a certain type of ball joint so the grease zerk is accessible IIRC.
I saw Opentrackers method and did away with the wedges.
Having done both, I'm not sure which would be more work to make, but I like the way the ball joint sits without the wedges.
I don't know if it's any lighter though, I boxed them while I was at it and welded the reinforcing plates on the area I cut and bent.
 
as i recall promotor sports uses a 23 degree angle on their wedges.

what shelby did on the race cars they built was drop the upper arm pivot point 1 1/4" and changed ball joints after every race.

when global west first started modding mustang upper arms, they cut a 15 degree wedge behind the balljoint, much like opentracker does with his arms.
 
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Our arms are given a 20deg bend. The cut is made in the side just behind the ball joint dome. IMO, this is a safer way to go than with a wedge and wedge shaped washers.

Here is some more info.http://www.protoworks.com/Mustang/Suspension/MustangSuspension.html

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Then the bracing is welded on the bottom and over the cut.

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John
 
I made a set of wedges, even made angled washers so the bolts wouldn't bend when I tightened the ball joint. You need a certain type of ball joint so the grease zerk is accessible IIRC.
I saw Opentrackers method and did away with the wedges.
Having done both, I'm not sure which would be more work to make, but I like the way the ball joint sits without the wedges.
I don't know if it's any lighter though, I boxed them while I was at it and welded the reinforcing plates on the area I cut and bent.

I cut the angle on the nuts for mounting the ball joints.

Too many projects, but I want to make a set Opentracker style as well so I can get rid of the wedges too.

John, I see in the second from the bottom photo you have replaced the factory part that bolts against the shock tower. Can you post any information about that?
 
the arm in that photo has a roller bearing rather than the stock metal bushings, which required a new cross shaft. an elegant solution for replacing the metal bushings, but rather expensive.
 
the arm in that photo has a roller bearing rather than the stock metal bushings, which required a new cross shaft. an elegant solution for replacing the metal bushings, but rather expensive.

Actually roller bearings are not very expensive. I expect the roller bearings cost less than $10. Retailers seem to want to charge a lot for them, though. The actual bar of stock that the bearings ride on shouldn't cost more than $50 in any kind of volume, but I would probably just make one.
 
Actually roller bearings are not very expensive. I expect the roller bearings cost less than $10. Retailers seem to want to charge a lot for them, though. The actual bar of stock that the bearings ride on shouldn't cost more than $50 in any kind of volume, but I would probably just make one.

true the bearings are not that exxpensive, and the bar stock itself isnt that expensive, but machining it can be. conside the price you charge for complete upper arms with roller bearings in them. a fair price though considering the work that goes into the arms, and the quality of the work done.
 
It is a roller shaft kit. I don't have the shafts made up in quanity, we are still a rather small shop. The shafts are made of 4140 chromoly and cost $100ea with bearings and hardware to produce. I know the price is high on them. It does take a lot of time and money to produce the roller UCA's. So far, the drag racers are enjoying them more than the road racers. One customer improved his 60' time by over 1/10th and 3/10th in the 1/4 mile using a full roller front suspension.

The first ones had a round shaft, the ones we produce now have a square shaft. Here are a couple more photos of them. The two black arms are our drag racing roller arm with no bracing and no ball joint angle change. The grey arm is the top side of the one in the other post.




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+1

Thanks for the help everyone. I'll have to land some old UCA before I try cutting and wlding them, but you never know. I bet most people take the brakes off of Granadas in JYs and not the suspension parts. :D



granadas use rubber bushings and the arms don't have provisions for the screw in bushings like the mustang arms. might work ok if you did the roller bearings instead but i wouldn't use them otherwise.