The upper control arms are stamped steel with a threaded hole to screw the ball joint into. The later ball joint for the disc spindle is larger than the drum brake smaller ball joint, so the control arms have 2 different size threaded holes. Look for the 73 and up control arm or buy new tubular ones.
Sure you can, I have made many mod's to my upper a-frames. I race circle track and many late model cars use screw in ball joints (chrysler) upper and lower sizes. Go to www.motorstate.com ball joint sleeves part # UBM40-3303 is the med size upper #UBM40-3300 is the large size lower. I cut the sleeve in half, 1 sleeve makes 2. So the grease boot will still work. Take off the old stamped threaded lip, open up the hole to your new ball joint size, weld on your new sleeve(threads) . Much stronger than the old stamped threads. Fix a striped out ball joint hole the same way too.
tnku now thats what i am talking about. in our hobby we don't take fool chances with ours or others lives we are looking for a good fix to a weak link. we are already running short on supply of upper control arms. i take safety as a first item, somesay we are dealing with our lives and lives of others, how about the relocation of rear springs and that coming undone. i am trying to find a supply of a arms that we could use unstead of going on the trash heap. i am in the media blast business and have done many a vehicle frame (most gm) not a knock a fact. that either had missing welds or not completed , most seem to be in the front frame area. also look at the mp k members now thats scary, but some how they made it. thanks again ron
I forgot to mention that ball joint sleeve is the same one used to make tubular upper a-frames. There are also 2 different types, 1 looks like a pipe coulper, the other is T shaped with a lip on top for welding to. Circle track guys have used tubular a-frames, both upper and lower for quite a while now. When I cut my sleeve in half the threaded length is the same as the stock stamped threaded length. I also know thru many laps on track that they are plenty strong. The right front takes alot of abuse. In crashes I have bent the ball joint stud, not uncommon, but not the upper a-frame. Much cheeper to replace just the ball joint, and I only use the good moog joints. I have worn out the cheeper ones in the matter of a few races. They just won't hold up like the moog brand. This setup is much, much stronger than the chebby bolt or press in style. The press in also have to be welded to stay in place. I know this site is primarily for drag racing, and I race circle track, but we both can learn from each other. Another thing I have had problems with is the poly bushings in the upper a-frames. On the right front after 2 nights of racing the poly, plastic squished out of the steel part of the bushing. Anyone else ever have this problem with the poly bushings??? Now my bushings are steel on steel with a greese zert, no more problems. Go fast turn left