Always happens, I expect it now. I decided to add positraction to my car, something I've wanted to do for as long as I've owned it. So I took the rear end out, then decided as long as it's out I may as well add disc brakes. The front end has had them since I installed the Jim Meyer front end during the initial build. I had been thinking about this project for a while and priced parts with weld on brackets. Then I found that Master Power Brakes had a bolt on kit. Twice as much but a lot less hassle and a better fit. This was all straight forward follow the instructions. The only 'machining' I had to do was on the axle registers. They were a few thou too large, so I used a new 4-1/2" grinding disk and carefully trimmed them until the rotors slipped on. I also needed some extra shims in order to center the calipers on the rotors. On to the posi project. I priced an EATON unit for about $500. That sounded pretty good. HAHA, sould have known better. When I got the third member out I found chips on several ring gear teeth. Ohoh, time for a new ring and pinion. I had always been a little disappointed at the high RPMs at cruising speed, so I tossed the 3.55 gears and bought a set of 3.08 gears. Of course now I needed all new bearings and an installation kit (crush sleeve, pinion nut, shims, etc). Besides parts, I knew I would need some new tools, since this was my first time digging into a rear axle. Ended up buying about $200 worth of tools, many of which I needed anyway. I bought calipers, a dial indicator, 3/4 drive breaker bar w/socket, an inch-pound torque wrench, bearing splitter, a set of seal drivers, and a few pieces of pipe for help pressing parts on. More later. Thanks for looking.
I built brackets to bolt the housing to my bench, built a wrench for tightening the side bearings, and a 'pinion holder' to help installing the crush sleeve. Thanks to YouTube I was able to find a great tutorial on rebuilding this 10 bolt rear end. A really good find since I really didn't didn't have a clue. Things went very smoothly, and I got pretty good at assembling and disassembling. After 3 tries to get the pinion depth correct, I had to buy more shims. I kept tearing them up when removing the pinion bearing. I started again, used the same shim thickness that was originally in it, and it was perfect! For some reason I thought it would take a thicker shim pack. When I finally got it assembled with the proper preload and back lash, I checked the pattern. It looked perfect to me. Again, I had never done this before, but it looked close enough to the pictures I had been looking at.
Here's the pinion holding tool I built. And a shot of it in place. I used a 6 foot piece of pipe for a cheater with my 3/4 drive breaker to get the crush sleeve installed. Easy Peasy LOL.
Yes, of the few original parts that came with the pile of parts I started with. 8.2" ten bolt. I think all full size Chevys 55-64 came with this rear end.
nothing like the original plans going from relatively cheap & easy - to Oh Sh-t, what did I get myself into?
A couple of other things needed attention. I had 1" lowering blocks on the car. When removed, I found cracks and mis-shaped holes where the spring center bolt rested. I knew I didn't want aluminum again, so I built a pair using some 1-1/2" x 3" tubing. I just cut the tubing to 2" wide, welded in a piece of plate, and drilled holes in the center. Put a short 3/8" bolt/nut on one side and done! Now I've got new solid lowering blocks, 1/2" thicker than previously. I also installed new properly sized u-bolts, 2-3/4" instead of the 3" bolts I had on hand when originally built. Much better. I got the car back together, and after adding about $50 worth of LS gear oil, took it for a test drive. Noticeably higher gear, and a real difference when I really get into the throttle. Only thing is, brake pedal feel really sucked! Here's another snowball. I never did have a very good brake pedal feel. It always took one pump to get a good pedal. I always assumed it was something about having disc brakes on the front and drums on the rear. NOT. I tested the master cylinder and sure enough, it wasn't working properly. I was also suspicious of all the fittings I had in the system, with residual valves, proportioning valve, brake switch, tees. Time for a new master cylinder and removal of the now redundant residual valves. I decided to use the proportioning valve combo that Wilwood makes, which includes a brake light switch. This is a great little unit for building brakes. I was also ready for an aluminum master cylinder, I was tire of looking at the rusty piece in my nice engine bay. I decided to get a slightly larger bore size, thinking I would need to push more fluid with the bigger calipers vs wheel cylinders. I ended up with a 1-1/8" aluminum master cylinder, which turned out to be a little bigger than the one it replaced. I was determined to make it fit, and finally got it finished. A good brake pedal makes me happy. Had to cut away some inner fender and a little under the hood. It's such a tight fit that I have to loosen it to add fluid. Almost impossible to work on with the Wilwood clutch master cylinder next to it. Finally got er done. What I thought was going to be a $500 project turned into more like a $2000 project Next up, my tires are almost 20 years old. Guess I'd better replace them before having too much fun. Might as well get wheels also. I'm thinking about 17" salt flat style. Thoughts?
I've heard that in the military they call it "mission creep". With car guys its always "since it's already apart, might as well replace/change/upgrade, etc. right up until the car is half apart. Lol
The Jalopy Journal
