How to idnetify a crank pulley for cast vs forged crank

Is there a quick way (e.g. bolt pattern, off set, etc...) to determine if a crank pulley is for a cast or forged crankshaft?

Not that I have ever heard of, Mopar changed the crank pulley bolt pattern in either 1971 or 1972 from non symmetrical to symmetrical on all the V 8 motors.
They didn't make and use different pulleys in the cast crank motors versus the forged steel crank motor That is probably due to cost and confusion on the assembly lines

If it's for a BB there's some info here:

http://www.440source.com/dampers.htm

Elliptical weight is similar on some SB's.

Your question doesn't make sense. Are you asking about the damper rather than the pulley?

Attached is a photo... are they the same for cast or forged crankshafts? Someone asked me once if a pulley I have was for a cast or forged crank. I was not sure how to distinguish, if there are different applications based on crankshaft. I know there is with and without AC or Power Steering.

Not that I am aware of other than casting numbers on the pulleys themselves, but I'm not sure that matters unless you are a "numbers matching" guy.

At least for RB motors, CAB is correct. In 1972, Mopar switched to a symmetrical bolt pattern on harmonic balancers (& pulley holes). Before that, there was one offset hole in both the balancer & the pulley.

As far as I know, the only mechanically important things are bolt pattern & pulley diameter & number of grooves/pullies on the part vs. your accessories (e.g. power steering, A/C, etc.). The pulley diameter would affect how fast your accessories turn (e.g. "overdrive" or "underdrive" your water pump).

The 440source list is a really good one.

The bolt spacing is different. There is one bolt moved over on a forged crank pulley. You know how the bolt holes only line up one way? Then you,have to rotate the pulley to get all 6 to line up? Ever had that happen?

Then the early 70's they bolt on without any specific orientation because the bolt holes are spaced evenly? Somebody sells a crank pulley with an oblong hole to fit both balancers. Does this sound familiar yet?

I'll try to get a photo.

The person who ask you that question is not a Mopar knowledgeable person The pulleys are different from some years to others, for instance in 1969 and later Mopar change the back spacing and diameter on the street Hemi pulleys 1966 to 1968 are the same, 1969 and later are not. You can swap the upper and lowers as a set and make them work, you can't swap only one of them though
As far as power brakes the on Mopar cars pulleys have nothing to do with the brakes, power or non power in other words the pulleys on a standard steering car with power brakes are the same as if the car had regular brakes if they both have the same motors in them
What does make a difference on the pulleys is power steering or power steering and air conditioning and the year and brand of the cars body style

Let's not confuse the matter with the hemi, different animal. LOL

Sorry, I meant to say Power Steering not Power Brakes. I corrected the post. Thank you for the feedback.

Here are a couple of pics of the BB pulley in question.

Examples

WRONG , you have a early pre 1972 pulley versus a 1972 and later pulley that both could have came on a forge steel crankshaft in either year motor
Trust us on this, your chasing absolute myths on this subject
I have used the early pulleys on the later balancers by filing and elongating the odd ball hole to make it fit on the later forged steel crankshaft balancers

[/b]

Originally Posted By NANKET

The bolt spacing is different. There is one bolt moved over on a forged crank pulley. You know how the bolt holes only line up one way? Then you,have to rotate the pulley to get all 6 to line up? Ever had that happen?

Then the early 70's they bolt on without any specific orientation because the bolt holes are spaced evenly? [b]Somebody sells a crank pulley with an oblong hole to fit both balancers. Does this sound familiar yet?

I'll try to get a photo.

WOW, file the hole, just like I said in my first post. Somebody sells that. I'm not chasing anything, I put up pictures to show the difference.

I didn't see that your post was not part of vinnyd76
Sorry

All is well! Too much info is good.

But Cab was right and you were wrong! You identified the PULLEY as "Description: Forged balancer with a forged crank pulley, all bolts line up"

The second picture showed the same forged crank balancer with in your description, a "cast crank pulley".

The point that Cab has repeatedly tried to make is there is no such thing as a "cast crank" or "forged crank" pulley.

There are pulleys and balancers made before the switchover date, and pulleys and balancers made after the switchover date.

Yes you can remedy the situation with a rattail file, no one argues that. But the pulley you are modifying was either made before or after the switchover date and that determines whether it has an offset hole or not.

Really, the only person to whom it would matter is a rabid restorer. But there are so many lies, errors and half-truths flying around the Mopar world that some of us try to snag them and hope to get them out of circulation.

R.

OK sounds good. Please tell use the "switchover date"

Pulley holes has nothing to do with cast or forged dampers, but just the year. I can fit a symmetrical hole pattern pulley on any damper as far is also symmetrical damper setup, no matter if casted or forged balancing damper.

BTDT.

The pulley setup and sizes changed allong the years due the diff engines setup and equipments itself. Some diff diameters considerations came out also to the rotation speed "upgrades" made allong the years to the diff miscelaneous parts for the engine ( alts, AC compressor, water pumps etc...)