I tried to install offset bellhousing dowel pins over the weekend. Found out that thats much easier said then done with the motor still in the car. I also found out that they seem to make them out of butter rather then steel. Good for conforming to the engine block, bad for getting them in. They either refused to go in, or one side of the dowel pin smooshed in, making the offset useless.

Are there any tips for getting them in? Do I have to take material off myself before installng them? I guess I could buy the kind that lock with a set screw. Id like to use the new split-locks that lakewood has, but the one with the proper offset seems to be perpetually out of stock.

 

Heat the block, freeze the pin.

 

The pins are at least two or three thousanths larger then the holes in the block. Ill have to stick one in a freezer and see how much it reduces the dimensions of the pin. Come to think of it, I wonder what dry ice would do? Probably would end up shattering them when I drive them into the block with all my luck.

The other thing, I suppose, would be to get some ones intended to 'slip' in and just stake them in the block.

 

hose it down with some r134 or a can of canned air held upside down

 

I measured, and the difference in dia. between the block and the pin is around 6 thousanths. Cooling the pin down to around -20 deg. F gets a reduction of around .5 thousanths. Im guessing that as long as I dont remove material im going to have to do some hammering no matter how big the temp difference is.

 

The block appeared to be around .620, which is slightly smaller then whats called for stock. Im going to assume that with the dowel pins being ~.626 I have to take some material off in order to have any hope of getting them in. I also assume Im looking for around .003" since the dowel pins are .625 and the holes are .622" under ideal conditions?

 

I figured out what was wrong. They where way too big diameter wise and totally mismachined. The offset wasnt even the same for two pins and they also didnt bother to even index the maximum offset with the slot on one pin, so theyd be damn near impossible to install. Another fine Mr ***-Gasket product

Now I remember why Im going through the trouble to use a stock bellhousing rather then an aftermarket. Unlike the aftermarket, at least I know the stock one was actually designed to fit on a car. Id never use anything from lakewood/mr gasket after the botched pins. It wasnt just those two, it was all four that I have. Not even close.

 

Get a McLeod 8630. They are already indexed & very rarely need offset pins.

 

Offset pins are often needed because of tolerance in blocks, and because of align-boring. You can easily have the most precise bell housing in the world and still need the offset dowels.

 

Yes... Block is off by a mile. It already ate my auto that i rebuilt for the car. Same thing with every other hole on the motor (starter bolt holes are REALLY bad). GM must have the mexican equivelent of Stevie Wonder doing their machining. I was thinking of trying the Morosos that supposedly 'slip' in next.

As for the bellhousing, I just opted to purchase the $200 something adapter plate for the TKO (still needed with the current aftermarket BHs?) and a used bellhousing. Its a little ratty and needs some TLC, although considering its 15 years old thats to be expected.