Measuring crank to bell housing alignment A904

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Abodysrule

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I'm going to mate a newly rebuilt 360 magnum to my newly rebuilt A904...I've never checked crank to bell housing alignment, what tool or methods do you all use to do that?

brian
 
No, I've never done this before or ever had any issues. The only reason I even bring it up is my B&M flex plate instructions say to do so, it says:

"Since the Torqueflite has a wrap-around bellhousing aligning the block to transmission, alignment must be done with the transmission case empty. Rigidly attach the indicator to the crankshaft and indicate on the oil pump bore in the case. Alternatively, you can use a manual transmission bellhousing to indicate runout."

So, Kim, that means I have to either gut my A904 or find a manual bell housing to measure runout?

In the alternative, has anyone ever had an issue with an automatic alignment issue?
 
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I spoke with Nick at A&A Transmission, he said in all his years working on trannys, he's only ever seen two instances of alignment issues with torqueflites. So apparently it is very rare. I suppose if you're building something really expensive you might do it.
 
I asked my friend who is very successful at Stock, and Superstock, he says in all the years he has never checked a Mopar Auto for alignment.

4 speeds are another matter, I needed offset dowels for my QuickTime bell.
 
No, I've never done this before or ever had any issues. The only reason I even bring it up is my B&M flex plate instructions say to do so, it says:

"Since the Torqueflite has a wrap-around bellhousing aligning the block to transmission, alignment must be done with the transmission case empty. Rigidly attach the indicator to the crankshaft and indicate on the oil pump bore in the case. Alternatively, you can use a manual transmission bellhousing to indicate runout."

So, Kim, that means I have to either gut my A904 or find a manual bell housing to measure runout?

In the alternative, has anyone ever had an issue with an automatic alignment issue?
U can’t use something different. It has to be what you’re gonna run in your car. Kim
 
Yeah, exactly, how would one every know/trust that the manual bell housing was true or correct or even the same as the auto?
 
I am guessing that an engine that has suffered main bearing block damage, and been line bored might be a candidate for re-alignment??
 
IMO, alignment with a bigfat convertor in there , would have to be off pretty significantly, to be a problem; unlike with a manual trans that has a pilot bushing in the back of the crank. When that business goes out of alignment you may get stiction of the disc on the splines which requires more than the usual clutch-departure to find neutral when stopped. and I suppose the hub of the disc could suffer; and I suppose the 4th gear brass might have a lil difficulty;
but honestly, the misalignment would have to be severe. And if really severe, I suppose those lil rollers in the back of the Input gear could do a number on the nose of the mainshaft.
But I mean ........................ I've only indicated a half a dozen Bellhousings, and only the one on my 367 needed anything and that's because the machine-shop that "align-honed" my block did a wicked number on it, and wouldn't come clean on the mess they made.
I did a 904 once, on a different engine, but it was within spec.
 
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Yeah, exactly, how would one every know/trust that the manual bell housing was true or correct or even the same as the auto?
Every single auto case & manual bellhousing can be different, autos seem to be more consistant, and the converter-hub to crank pocket is not as close a tolerance nor as critical as the pilot bushing to input shaft on a stick.
 
First off your tranny has to be gutted. Then u will need a dial indicator and magnetic base. Kim

Another crucial alignment check that is often overlooked, especially on 4 speed set-ups, is to verify that the mating surface to transmission face is square to the crank centerline. I can't visualize how you would check that on an automatic. My '70 E-Body with RB has a scatter-shield that was significantly off, and required shims to get the bellhousing square.

Shims.JPG
 
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