So i got the 700R4 matted with my Straight 8 via some adapter plates on my 51 Buick. i decided to raise the motor/trans about 3/4" for oil pan ground clearance. if i need to raise the drive shaft tunnel, that's fine cause i got no carpet right now. So i have to install a "modern" exposed driveshaft rear end to replace the torque tube style one it had. How do i properly posision (square) the diff under the car? Can somebody link me to a good set of procedures or step by step on locating the diff under the car so that it goes down the road straight and so that the wheels are correct under the wheel archs? i also need to know how to check for the tranns / diff pinion angle? i am running airbags so i know there will be some side to side movement as i change the ride hight. i plan on setting it up to the "driving" hight that i want. Thanks, Yaril
Well, I don't know if it's neccessarily the right way... but here's what I did on my 53 F100... I'm running airbags as well, also a triangulated 4 link. If I did something wrong, I guess I'll be schooled (which is a good thing, before it goes on the road)! We set the truck up at ride height. We knew the wheelbase was 110", so we started from there, measuring straight back on each side, from the grease plugs on top of the control arms. They seemed to be right in the center of the front spindle. We didn't go off of the spindle itself, cuz there was no way of really if they were aligned or not... from here, with string we were able to take some trinagulated measurments from the front, accross the frame, to the opposite side, making sure that 110" number was square on both sides. the frame rails got a little wavy as they went back.. we were able to get pretty damn straight, but that cross measurment made up for any imperfections. Also, the 4 link will help with any fine tuning. We were also able to use that cross measurment to get the rear centered, by taking the numbers from a point as close to the hubs as possible. Granted it was much easier with the body off the frame, but maybe the same idea can be applied in an easier fashion. Sorry, I don't have pics of the procedure itself, but here is the result... It's basically just tacked in for now. It needs to be beefed up at the upper front 4 link mounting points. www.blowupthespot.com/ford hope this helps a little. -B
hey bro just eyeball it, whats the worst that could happen j/k what rear are you using? if it was from a car with rear leaf springs there should really be a guess work involved
If you have a concrete floor and a few jack stands, put the whole works up in the air. Use a level across the frame and get it as close as you can with shims or whatever. Use a plumb bob off the bottom ball joints (doesn't really matter what point, just so long as you use EXACTLY the same spot on both sides). Mark these points on the floor with a Sharpie (sweep first!). Now drop points off the center of the rear axle flanges (axle at ride height). There's usually a dimple in there you can line up with. Moving everything to the floor eliminates the need to measure around things, and it's easy to figure side to side, lengthwise, and diagonal by just moving the tape measure around. Front end doesn't really need to be at ride height, because those points are only for reference measurments, BUT look real close and make sure nothing's bent that would throw one side off. This is a fun project! I've done a lot of 9" swaps on drag cars and they go straight, so it works.
thanks guys. i feel much more comfortable doing this job now. my car is on a cement slab and on 4 stands, i will make sure the chasis rails are as parallel to the ground as possible. Then i will verify all exsisting cross dimensions to make sure i am working with a square chasis. i have to go out to the junk yard and buy the rear end, so i will keep writting back on this thread as i make some progress. Maybe someone will find it usefull in the their project. Thanks again, Yaril
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