Bellhousing Alignment

Well, I measured and I am having a hard time getting what I feel are consistent, accurate readings. But I feel these numbers are pretty close to accurate. The distance between the pins in the block is 15.38" and the bellhousing is 15.41". That gives a difference of .030 which I think is not quite correct. I think it is a little less than that which is why I question the accuracy of these numbers. At some point I'm going to have to come up with accurate numbers to know what offsets I need.

 

Yea my bellhousing reads about 15.41+ center of the hole to center of the hole straight across with a tape measure thats wierd?

 

Well, I'll have to see how this next bellhousing measures and fits. Two things I've noticed about this housing. One is the holes for the pins are not centered. In other words, if you look at the casting, each hole, be it pin hole or bolt hole, has a chamfer to it. All the through holes for the bolts line up in the center of this chamfer. The pin holes, however, are not centered within their respective chamfers. Secondly, on a couple of the bolts holes, there are "thread tracks", for lack of a better description, where it looks like the bolt hole didn't align with the block hole properly and so the threads cut into the housing as the bolts were installed through these holes.

Anyway, I'm anxious to get this next housing. It will either answer all my questions or confuse the issue even more. I will post either way what it tells me.

 

Well, I figured I'd give an update to my bellhousing issues for all you that couldn't sleep over it.

I bought a second bellhousing and it was pretty close to identical to the first one as far as fitting the pins. So no fix there. I did, however, get the first one on. All it took was mild persuasion which I was afraid to attempt before.

I have checked the runout of the crankshaft to the center of the bellhousing and it seems to be off by about .050". I am gun-shy about trying to get the pins out of the block. The engine is in the car and will remain that way so most methods of removing the pins I'm aware of aren't an option. I'm afraid if I try to remove them with vise grips or something, all I'll manage to do is chew them up. So I am going to enlarge the holes in the bellhousing to 3/4" and fabricate eccentric collars to fit over the pins to correct the alignment.