Guys, I am moving sLowly but slowly on the RPU. I am to the suspension and I am looking for something that will work well. Now I have figured out something that will work, but maybe not well. I have the bed section "Z'd" and have a set of coilovers. The body is channeled about 4 inches. The bottom of the rearend sits 5.5 inches above the frame rails/Body. No room for a 4 link that is over 12 inches without hitting the body. Cannot go to the outside of the body without hitting the tires. A buddy of mine convinced me that a 2 link is the way to go. Now I am not so sure. It will physically fit and operate, but you are really making both sides of the rearend move as one piece. Two up and down pivots connected to the inside frame rails and the other end welded to the rearend. There is no independent movement of the rear wheels. This is fine if all the bumps and bounces hit both wheels at the same time, and if you are running a spool. But does that really happen. Just the torque of the single track is a lot of stress. What am I missing. I have started looking at my 69 chevelle for answers. Any one have the obvious solution?
2 link probably bad unless the front ends of the links are very close to the center line, near enough meeting at the back of the trans. I have has a simarlar problem with fitting the axle in my 32, where additionaly the drive shaft was going to be so short that there was not going to be much movement up and down, so I opted to go the IRS route, which solved both problems at a single hit. A lot to be said for going IRS if things are tight for space.
I built a home made triangulated 4 bar with air bags on my '27 RPU. I have more information, let me know if you are interested.
Brandon, The triangulated upper bars eliminate the panhard bar. I have this set up on my '27 Model T RPU and on my '30 Model A Sedan. I built both of these from scratch. The '27 has air bags in the rear, the '31 has coil overs. I prefer the air bags, much less harsh of a ride. I have attached pdf's of the drawings I created for the '27 ch***is. I created drawings prior to making the parts, CAD is what I do for a real job. Also worth noting is that during construction I built a wooden fixture to hold the 4 bars to ensure everything stayed in the correct geometry when tack welding the brackets to the frame and the rear axle tubes. In case you are wondering the frame started out as a set of American Stamping '32 Ford rails. Front crossmember is an aftermarket 2" dropped deuce type that I narrowed to fit the little T body. All other boxing plates, brackets crossmembers etc. I fab'd up myself. I basically mocked up everything using cardboard templates and then transferred them to CAD. I had the brackets burned on a CNC burn table that I had access to at the time. Let me know if you have any other questions. John
The Jalopy Journal
