Bell housing bolt holes

[John M.]

I would appreciate it of someone could measure the diameter of the bell housing bolt holes and post. I'm at work, the bell housing is at the shop.
The reason for this is that I'm helping a friend put a Tremec 5 speed in his 67 and he's bought a repro bell housing (LIC I think.) The toltal allowable runout, alignment of crank center to transmission input center is 0.004". We measured 0.019"! So we have cam shaped dowel pins to re center this thing but I may need to ream the bolt holes to move it that far. The bolts are 7/16 but I need the thru hole diameters to bring the correct reamer(s).
Thanks John Mcrae 30025

[Joe L.]

Re: Bell housing bolt holes

I would appreciate it of someone could measure the diameter of the bell housing bolt holes and post. I'm at work, the bell housing is at the shop.
The reason for this is that I'm helping a friend put a Tremec 5 speed in his 67 and he's bought a repro bell housing (LIC I think.) The toltal allowable runout, alignment of crank center to transmission input center is 0.004". We measured 0.019"! So we have cam shaped dowel pins to re center this thing but I may need to ream the bolt holes to move it that far. The bolts are 7/16 but I need the thru hole diameters to bring the correct reamer(s).
Thanks John Mcrae 30025

John-----


The bolts are not 7/16"---they're 3/8"

The bolt holes are of 2 different sizes. The upper 4 (2 on each slanted surface) are 29/64". the lowermost bolt hole on each side are 25/64".

[John M.]

Re: Bell housing bolt holes

Thanks Joe,
We got the assembly together today (the bolts are 3/8, thanks). We were able to center the bellhousing with the offset dowels but it's not at all straightforward. The dowels have to be sanded until they are a slip-fit in the block and the housing so that you can rotate them with the bell housing attached, moving the housing around until the dial indicator shows it's centered. This is what happens when you use aftermarket, Chinese, reproduction parts.
John

[Larry M.]

Re: Bell housing bolt holes

Thanks Joe,
We got the assembly together today (the bolts are 3/8, thanks). We were able to center the bellhousing with the offset dowels but it's not at all straightforward. The dowels have to be sanded until they are a slip-fit in the block and the housing so that you can rotate them with the bell housing attached, moving the housing around until the dial indicator shows it's centered. This is what happens when you use aftermarket, Chinese, reproduction parts.
John

John:

Glad you got the offset dowels installed and the bellhousing dialed in. Don't know what dowels you used, but the most highly recommended ones are these:

http://www.robbmcperformance.com/products/dowels.html

If you find that you need to remove the bellhousing, or for the future, I highly recommend these dowels. They are also re-packaged by Lakewood, and sold under a Lakewood part number as well.

Larry