Thread: How to build an early hotrod frame

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On the transverse rear setup you've got pictured the rear crossmember is a Model A, any of the four years of production are esentially the same. The high arch in the center spring is also Model A design (if not original). These are particularly popular when installing a quick change rear end because the high arch allows room for the rear part of the quick change housing to move up and down with suspension travel. A rear cross member from any of the later years ('32-40) could be used, but then the flatter arched spring that is commensurate with those years should be used as well. '35-36 rear wishbones are prized for their integral spring mounting brackets that hang to the rear of the axle housing (The pic below is the later model hanger than '36 that's integral to the axle rather than the wishbone but gives you the idea, I'll post a '36 pic when I find a good one). Also pictured below is a low arch transverse spring clamped to a rectangular tube fabricated rear crossmember.

I'll add another picture here that goes along with either your coilover or pocket spring examples for showing control arm arrangement. The pictures Brian has put up are typical of a parallel 4 bar arrangement. Another alternative that eliminates the need for the panhard side locating bar is called a "triangulated four bar". The triangulation of the upper bars provides the axle side movement limiting. Not very traditional, but effective. Routing exhause can sometimes be a challenge.