4 speed crankshaft

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1qwkgts

1qwkgts

daveydart
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I'm building a 340 Swinger 4 speed that was purchased in pieces... "project." The motor that came with the car is a date correct 340. My question is: is there a difference between a 4 speed crankshaft and an automatic and if so, what is the difference? (picture?) Also, what are the correct bolts to hold the flywheel to the crank? (picture?) Finally, I had to buy a flywheel. The one I got has number 2264598. Is that correct?
Thanks so much for any help.
Dave
 
4 speed crankshaft has a hole bored in the end for the pilot bushing - automatic does not
 
They all have "holes." But some automatic cranks are not as deep as they need to be, or not finish machined to finish ID. You used to be able to buy undersized pilot bushings. It used to be common to cut 3/8" or so off a 4 speed shaft to accomodate a shallow pilot hole.

If you do not actually try a bushing it may not be obvious just "looking"
 
You said it's date correct, but what date is that? Some '72, and all '73 340's are external balanced.
 
if the cranks depth is good you can use a the National bearing FC69907. This bearing fits in the register for the converter. It uses the roller type bearing instead of the bushing that would normally be used as a pilot.
If the depth is not deep enough you will need to remove grind off 1/2 to 3/4 of an inch from the input shaft of the trans. I do not know what the minimal spec is for use with auto-crankshaft with 4-spd trans though.
 
Here are some pictures of the crankshaft. I think it is correct for the 4 speed, but I just want to be sure.
Thanks,
Dave
 

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I don't know how to tell from that. I may be wrong on the SB but on many on the BB some of them were 1/4 to 3/8 lacking IE you had to either drill them that much deeper or cut 3/8 or so off the shaft. Only way to tell was to measure the hole. Only way I knew to do this was to compare to a known crank or to measure in an assembled bell / engine situation

Likewise the OD of the bushing, "you could tell" if a bushing was going to fit a finished hole

As someone mentioned if the hold is deep enough but simply undersized, you can use the later converter register bushing
 
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