6 pack crank / flywheel vs non six pack

[eldubb440]

my question is ..... how do you id the back of the crank? is there a balance difference? and is it possible to bolt on the wrong flywheel? is the bolt pattern the same?........ thanks

 

[gkent]

There is no difference between 6-pack crank and flywheel vs a standard 440 crank and flywheel.

Balance difference (flywheel) ... they should all be "zero" balanced BUT that's not a given if the flywheel came off a previously rebuilt motor.
Balance difference (crank) ... 6-packs used a heavier rod so the bob weights would be different so the crank balance will be different than a non-6 pack crank.
Wrong flywheel ... yes, there are 130 tooth and 143 tooth flywheels
Bolt pattern ... same except Hemi - and you'd find that out real quick! Not sure if small blocks have the same 6-bolt pattern as big blocks.

 

[RemCharger]

Can't I'd a crank from looking at the back of it.
6 packs had different balancing depending on year. Newer ones had a special balancer. (And therefore likely had a offset balanced TC or FW, although I can't confirm 100%).
I have gotten a 6 pack crank/rods balanced to internal. It can be done, and is recommended.
All 6 bolts are the same, SB, BB

 

[Cranky]

Not sure if small blocks have the same 6-bolt pattern as big blocks.

IIRC, they have the same 6 bolt pattern....

 

[R413]

The 1970 and 1971 440 HP and 6bbl flywheel and converters are different than440 standard and 383. Flywheel has material milled off of it. Extra weights on converter. The special balancer with the oblong weight, looks similar to a cast crank balancer but they are not the same.

They are externally balanced engines from the factory.

They can be change to internal balance. So now 52 years later who knows what’s been done?

Yes SB and BB 6 bolt crank bolt pattern the same.

 

[eldubb440]

The special balancer with the oblong weight, looks similar to a cast crank balancer but they are not the same.

like this one?

 

[440 PHIXX]

like this one?

View attachment 1245021

Yup. That’s a heavy rod balancer

 

[Curiousyellow71]

These are the flywheel/convertor balancing differences for small and big blocks.

 

[Cranky]

like this one?

View attachment 1245021

Timing cover is different than the 'regular' 440's.....different timing tab.

 

[1 Wild R/T]

There is no difference between 6-pack crank and flywheel vs a standard 440 crank and flywheel.

Balance difference (flywheel) ... they should all be "zero" balanced BUT that's not a given if the flywheel came off a previously rebuilt motor. Heavy rod 440's had a different flywheel, the crankshaft balance was the same as a LY rod 440... I have a Chrysler Memo explaining the change but don't have time to dig it up...
Balance difference (crank) ... 6-packs used a heavier rod so the bob weights would be different so the crank balance will be different than a non-6 pack crank. Incorrect, see my above post
Wrong flywheel ... yes, there are 130 tooth and 143 tooth flywheels
Bolt pattern ... same except Hemi - and you'd find that out real quick! Not sure if small blocks have the same 6-bolt pattern as big blocks.

 

[1 Wild R/T]

Curious Yellow 71's post shows the correct flywheel.. I think thats Brewers website..