So I'm replacing the rear end of my 41 ford deluxe. New diff. and new leaf spring kit. I understand from reading a lot of the pinion angle post. Having leaf springs and it being a daily driver that my pinion angle should be equal and opposite the trans output shaft angle. e.g. 3down 3up. I also understand that i should have my car at ride height to check and set these angles. Now here is the question. With the way my car sits at ride height i can't get to the output shaft of my transmission to measure the angle. Can i take the measurement from the carb plate? It is suppose to be level by what i understand but with my car I'm not so sure. Also if i can take the measurement at the carb plate what would the angle of the output shaft be on a chevy 350 with a TH350 with the carb plate a 0 degrees. I've read both 3 degrees and 5 degrees. I've read so many pinion angle post my brain might pop. So the simpler the answer the better
I just put a new rear leaf kit and rear end in my 42 Tudor and the installation instructions said 6 degrees for the spring pads as the rear will move under load.
If you can't get to the output shaft, I would measure the angle at the top edge of the valve cover (***uming they're flat) instead of the carb plate. I've done this before on a 350/350 combo and checked it against the output shaft. Both results were the same.
Is that 6 down or up? have to say first time i've read of 6 degrees. Most of the post say 3 up on pinion. Some say 3 down due to spring wrap. But that's mostly on race applications.
Measure the motor wherever you can see; valve cover, oil pan lower rail, etc. The optimun angle of the motor is not really what is the 3 degrees. The angle of the motor is more related to keeping the carb, sort of level. The angle of the u-joints is "optimum" at 3 degrees. You measure the angle difference from the engine to the driveshaft. Same is true with the rear of driveshaft- to-pinion; try to keep that angle as close to the front joint angle if possible. You can get away with a bit less or a bit more than the 3 degree optimum.
You can use the ****** starter surface. Won't get any "equal but opposite" angle thing as with using the valve cover surface.
Thanks that was the last measurement i needed before i got my spring perches welded to my new rear end. Now i can finish this swap this weekend
Yeah i understand the concept of setting up. The problem is taking the measurement at the transmission tail shaft to get the proper angle for the pinion. While at ride height i have no access to the tail shaft to take the measurement. But if i can take it at the starter housing and it matches the trans output shaft angle thats all i need.
I ***ume by ride height you mean this s a roller with body on it and its sitting on on all four tires...if this is the true then use some 8x8 square blocks of wood about 2 to 3 feet long to go under all four tires and you still have ride height but allowing enough room to get under it to tailshaft.. .and be sure to cut wedges and nail to front and back side if tires to keep from rolling. Posted using the Full Custom H.A.M.B. App!