467-Ratman

Just talked to my engine shop today, and my big block with the merlin heads has two cracks in the crank. I need to buy a new crank, but what should I buy. What is the story on cast steel versus forged steel and cast iron. I wan't my motor to have about 450+ hp, do I need a forged crank, they are expensive!!! Thanks as always for the great help.

BigBlockVette

When I rebuilt my big block last year, I installed a forged crank, casting #6223. I bought it from a place called Crankshaft Craftsman in Detroit. Phone number 313-366-0140. They wholesale to the public, I paid $188. (out the door, no core) for mine. Very Happy with my purchase from them. All they deal in are cranks.

Dwayne


[Modified by BigBlockVette, 10:10 PM 12/12/2001]

gkull

Get on the internet. I would go for a 5140 forged. it might be time for a 4.25 stroker :)

Flareside

No Tom, you don't need a forged crank for 450hp in a big block. Cast is fine. What size engine are we talking about, a 454? Summit has a cast 454 crank for around $280 (although it may be made in China if that bothers you. Some don't like import engine parts). You can get forged steel GM for around $550.

Oh, there is no cast steel. Forged steel or nodular cast iron.

-Joe



[Modified by Flareside, 10:15 PM 12/12/2001]

467-Ratman

If I went to a stroker crank, 4.25 what kind of cubes would that be? Any other things to do for the block with a big stroke?

Tom454

Tip on cheap cranks-

Be sure to read the fine print. An extremely cheap price is usually a sign that the crank is a re-grind, not new.

Besides the main & rod bearing journals, cranks wear on the counterweight surface where the rods rest. If the wear is severe, even with new rods, you may have too much rod side clearance. A re-ground crank with this problem is virtually useless.

Let the buyer beware.

Tom

L71

steel all the way, and must be balanced, don't get cheap. But if its just a driver and won't see punishment go with the cast

mountainmotor

I would follow Big Block Vette's advice or contact Competition Products in Oshkosh,Wisconsin and get one of their Cat cranks.Yes Cat not Scat.I have a Cat crank running in a 600 hp boat in a former customers motor.Not a problem after two years.