Engine Balancing

[Jacksboys]

I just want to make sure I am correct about this:

When dealing with all big blocks (both B and RB), if you have a forged crank it will be internally ballanced and if you have a cast crank it will be externally balanced.  Is this correct?

Thanks

[Chryco Psycho]

basically yes , most  cast cranks are externally ballanced , except the 383 2 bbl in 69 - 70
most steel cranks are internally balanced except the 70 -71 HP / 6 Pack  engines with the heavy rods 

[NoMope Greg]

Ummm...teachable moment here - CP, can you please tell me the difference between external and internal balance?  Internal is with mallory metal and/or milling the counterweights and external is on the flywheel?   

[Chryco Psycho]

internal means there is enough weight on the crank counterweights to balance the the piston & rod weight , external means the damper & flywheel or torque converter have weight added to balance it

[Jacksboys]

basically yes , most  cast cranks are externally ballanced , except the 383 2 bbl in 69 - 70
most steel cranks are internally balanced except the 70 -71 HP / 6 Pack  engines with the heavy rods 

Thanks Chryco  

Is it easy to spot the 70 -71 HP / 6 Pack  engines?  I mean if they are not in a car.
Thanks

[Finoke]

internal means there is enough weight on the crank counterweights to balance the the piston & rod weight , external means the damper & flywheel or torque converter have weight added to balance it

Well said 

[Chryco Psycho]

the damper is offset on the HP engines , it is not difficult to spot when looking for it

[Jacksboys]

the damper is offset on the HP engines , it is not difficult to spot when looking for it

Ok thanks