I have a friend working on a cobbled up 70 "B" body 440 4-speed car and the pilot bearing he purchased has an OD that is too large. From the casting numbers on the block (36XXXXXX)it appears to be of the 75 - 77 vintage. Does anyone know how many different pilot bearing sizes were used on big block 4-speed mopars.

Is the crankshaft actually drilled for a 4 spd input shaft and pilot bushing? Not all of them were.

And, if it wasn't drilled/reamed to size for the bushing, then a better than stock solution is to use the roller bearing from a late model truck. They are about $12 new at any parts store, and fit into the register for the torque converter hub, eliminating the need to machine an auto crank to accept the stock bushing.

Yes, it sounds like your crank isn't finished drilled for a four speed. For some reason Chrysler rough drilled all cranks but didn't finish drill them for the pilot bearing.

Just get the bearing that goes in the hub. I bought mine from Mancini, but lots of places have them. Just make sure the crank is drilled DEEP enough, sometimes they aren't drilled deep enough either. If not you can drill it deeper or trim the input shaft on the tranny.

http://chucker54.stores.yahoo.net/marapibe.html

I don't like the pilot roller bearing. The rollers can fail and stack up. Then you ruin your input shaft. Get the bushing that fits in the crank hub from a late model pickup. Grease it well and you are good to go. If it has had a 4 speed already, then the crank is probably drilled deep enough already. It should be about 1.750" deep to accept a stock input shaft.

There used to be a thin wall pilot bushing for the un-machined cranks. Pioneer brand? NAPA may be able to find it.

I much prefer and run a roller bearing in the TC hub as posted above. Its the same basic setup used in all current production MT vehicles.

The car has a 4 speed in it now and is in the process of having a clutch put in it.

Basically everything was wrong, clutch disk in backwards, Chevy head bolt welded on for the throw out rod. We have no idea how it actually ran. So my buddy, who owns the garage, agreed to pull it apart and found this cobbled up mess. The owner has no mechanical knowledge. So my buddy is now trying to put it back to a correct configuration. So far everything he with the clutch and the transmission he has touched is either junk or wrong.