Thread: How to build an early hotrod frame

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There are other ways to mount a beam axle front end, but they are getting to the point of 'outside my experience". I know that some people have ran coil sprung front beam axles with success, but since I am trying to stick to things that I have personal experience with, I am not going to cover them.
It is now time to move to the other end of the car, and talk about the way we will support the rear axle. I am not going to try and cover the "exotics" here, like Jag or Corvette IRS. We will be dealing with the 3 main ways to support the rear axle, namely 1---coil over shocks, 2---home built coil cups with the shock up thru the center to hold the coils in place, and 3---transverse leaf spring set-ups. speaking from personal experience, first let me deal with coil over rear suspensions, which of course refers to aftermarket shock absorber and coils springs built into one unit that will bolt to the frame at the top end and to the outer ends of the axle at the bottom end. This tends to be the most "mainstream" method of hanging a rear suspension, and of the 3 types I am going to deal with, probably the most expensive. These "coil over" units range in price from $400 a pair at the bottom end, up to $1000 a pair for the high tech polished billet units built from unobtainium. They are relatively simple to mount, requiring a set of brackets being welded to the rear axle housing tube on each side, and a matching set of brackets which are welded to the crossmember (which again generally sets directly above the rear axle centerline).They are generally supplied with a round "loop" at each end, which will receive a bolt thru the loop with rubber or neoprene bushings. There are some applications where the rear crossmember can be directly above the rear axle, and as shown in the attached picture, there are some applications where the rear crossmember can actually be offset from the centerline of the rear axle. this depends to a great deal on the shape of the floor pan in the vehicle which you are building.