413/440 crank pilot/register dimensions

I have seen conflicting numbers on crank end bores. This is the A727 auto from factory so probably not machined for manual.
I'm looking to machine a metrology part to check crank center dimensions vs the dowels - but I don't have the trans off yet and might not for some weeks.
I have the ZF trans pilot side done.

What exactly are you looking for ?

What measurements.

In the pics above, left one has .875 & .938 and the other .890 and .850
The larger might be for the manual shaft bushing, and the other the automatic?
The 2.225 depth indications also disagree on how it is measured.
I have the steel flange adapter but it is bored for the ZF's TC nose

The crank bore, when finish reamed for a factory bushing, will measure .9375" (15/16"). For the crank that isn't finish reamed for a bushing, they usually measure .915" which is the size the aftermarket bushings are made for but I've measured crank bores that weren't either. IOW, it seems that the initial pilot bore is inconsistent, the final ream size, however, is always .9375".

As to the depth, I've never measured it.

Thanks!
It looks like I'll have to wait until I pull the 727 to be certain.

i just measured a 440 crank in an engine i have on the stand.
it happens to be an eagle 8 bolt crank, so take these dimensions for what they are worth.
the torque converter register bore is 1.812 in diameter, and .668 deep.
the second pilot hole is as Mr. Kunkle said, .9375 in diameter, and is 1.050 deep from the .668 converter depth, or 1.718 deep from the flange.
the final pilot hole is .845 in diameter, and is 1.700 deep from the .668 converter depth, or 2.368 deep from the flange. this is the depth of the diameter to where the shoulder of the drill stops. it does not include the drill taper or point depth.
this is just what i have on my crank that is easily measurable.
your crank will vary..............[just thought of something funny after i wrote that. ]

Don't worry about installing a pilot busing, I switch to the 1996 and newer pilot bearings, way better to use and install

Was it from a manual or auto?

I'll bet that all the aftermarket cranks are drill for the stock bushings, maybe not

I'm machining a centering tool to check the shaft alignment of crank to input shaft of the 8 speed auto. It will capture the new dowel pins precisely and I can the measure any difference when mounted on eng vs bellhousing

Ray, my crank was used with a 727, but being an aftermarket crank, i figure it might be usable for both ?

Probably, or at least one would hope, right?

John Vinson got back to me: (http://www.jvxracing.com/CustomerCars.htm)

with even more slightly different dimensions...
Since I want the alignment plug to be within .001 fitment it looks like I'll wait to pull my trans, then clean up and measure.

it will be interesting to see what you find out.
please post the numbers you come up with on your crank.
it looks like quality control may be all over the place.

Good luck on getting it that close

It will be once I clean it and mic it.
I'm also now considering just mounting the adapter and using the crank spacer which is lathed precisely. It sticks out 3/4" from the crank though so I'll have to mod the part that indexes the dowel pins.
Additional benefit is knowing the eccentricity if any of the mounted spacer.
Alignment spec is <.005" and ring runout .0005 per inch diameter, so I'll be checking that too of course.

One of the hardest part of doing this for me was getting the zero set on the micrometer properly to find out what part of the circle was offset from the center of the crank
Have fun, stick with it and let us know how far yours was out and which offset bushing you needed to use to get it the way you wanted it

My design idea was to use a 1" nose on the crank side and another over the input shaft end, then use feeler gauges to check offset from the dowels via a 1/4" plate:

If your going to use a automatic tranny with a stock type or race converter I wouldn't worry too much about it being dead nuts on input shaft to crankshaft center line due to all the built clearances in the front pump and flexplace centering the converter to the crankshaft center.
If the converter will slide into the back of the crankshaft easily installed in the tranny with the tranny hooked up to the motor and the converter bolts install easily, I would use it the way it is :: up:

The ZF 8HP70 has a long input shaft (all the way to the rear drum) and zero wiggle. The adapter plate is a stiff 1/8" steel as well so less flex. JVX says .005 is OK, more requires the .007 offset pins.
I would guess that the A727 has more "flexibility".
We did have a 73 Jeepster Commando that cracked 2 flex plates because the OEM adapter (AMC 304 to TH400) was not true.

One other dimension I'd like if possible - the offset from the face of the flange to the block mating surface.
I'm assuming is is ~.61 from what I could find and the B/W drawing posted earlier.

I'm now making an offset metrology plate (blue) and one plug(red) for the crank adapter from JVX with the same .697
diameter as the input shaft.

using a straight edge from the crank flange to the bell mounting surface in several places, i got 0.600 [six hundred thousandths]

Awesome, thanks.
I was just estimating from the brewersperformance drawing, scaled to the dimensions there, so .610 was not bad.