I need to find out what the dimension is from the block mating surface that the transmission/bellhousing seats on, to the surface the flex plate bolts to.

I have measured a couple of times.
My tools for measuring it are somewhat primative, so I want to make sure.

Anybody got this dimension on hand?

CJ

_________________
Part of Tyrde-Browne Racing

On the engine I've got on the stand, I'm getting from 0.570" to 0.650". The larger number is repeatable on the driver's side of the engine, the smaller is repeatable on the passenger side.

Looks like the factory machine work and line bore are pretty lousy. I'll have my machine shop check the blocks we have set aside for the Dragster, and make sure the line bore for the crank/cam is perpendicular to the mounting surface.

CJ

_________________
Part of Tyrde-Browne Racing

0.570" to 0.580"

Got a bit tighter.

CJ

_________________
Part of Tyrde-Browne Racing

I am by ANY stretch of the imagination an expert, BUT wouldnt that measurement also change with the fore/aft movement (thrust) of crank? Sure, not any discernible amounts, but just sayin'....

_________________
MRO....

Cheap, Fast, Reliable.... Pick 2...

The thrust could indeed allow for variations in the measurement.

In this case, the engine being measured is a freshly rebuilt 225 with new thrust, and the crankshaft has not been disturbed by the meaurement itself. The bearings are loaded with pre-lube, so the crank is not likely to move much with little axial force placed on it.

What I'm finding is, the surface machined for the transmission to mount to is not true. The area I was measuring was determined by the position of the engine stand arms. When measured across the surface adjacent to the starter mounting area, the largest discrepancies were noted. Since the engine is being held in place to an engine stand, there is a certain amount of strain on the mounting surfaces of the block. Basically, the engine is "sagging" on the stand.

It will be interesting to drop the engine from the stand and make the same measurements to detmine how much deformation is present due to the support method. Simply hanging the engine by the head mount points may erase some of the variation.

Interesting, huh?

CJ

_________________
Part of Tyrde-Browne Racing