Mustang II findings and questions
I'm building a 65 Mustang street car with a 750hp 521 and a Mustang II front end that consists of a Rod and Custom Motorsports crossmember, my own chrome-moly upper control arms, and soon to be built or purchased and modified lowers.
One thing I noticed when digging into the task of buying or designing lower control arms is that you can't just use any tubular lower control arm on any crossmember. The Heidt's lowers are designed for their crossmember (I *heard* it was 3.375" wide from front to back). The RCM crossmember is 4". If you use a Heidt"s lower on it, it will move the balljoint forward .313" with respect to the crossmember centerline. If you use a crossmember that is less than the Heidt's crossmember width you can use the Heidt's lowers provided that you space the control arm properly to put the ball joint on the crossmember centerline.
So, the fix is to chop off the bushing sleeves and use rod ends which are thinner than the rubber bushings. This should provide just enough extra room to put the control arm where it needs to be. I have a feeling few people consider the ball joint location when purchasing a tubular lower. Note that this only pertains to those purchasing tubular lowers that eliminate the strut rod.
This also scares me because the RCM website is selling lowers that look just like Heidt's, so I am assuming that they are Heidt's. I could be wrong, though.
So here's my question. Does anyone know the diameter and wall thickness of the tubing that Heidt's uses on their lowers? If I can't thread it for a 5/8-18 rod end I'm screwed and must build my own set!
Also, I wasn't too impressed with the person who told me that the Heidt's crossmember was 3.375" wide. Does anyone have one around that they can measure so the info can be posted here?