450 to 500 hp 4 speed crank choice

[K.O. SWINGER]

I would like seasoned opinions on crankshaft material choice for a 450-500 hp 4 speed. Big clutch and 275 drag radials am considering a 3.58 stroke 340 . My question is would you feel good with a high-end cast crank like a 900 series scat or would you just bite the bullet for forged and never look back.

 

[dano]

For that I'd go forged for the piece of mind and growth potential.

 

[NC Engine Builder]

Forged would be my choice

 

[pittsburghracer]

If it wasn’t a factory cast crank I wouldn’t buy anything cast.

 

[QuickDart360]

If it wasn’t a factory cast crank I wouldn’t buy anything cast.

The stock 360 crank takes almost anything you can throw @ it! Aftermarket not so much. Maybe with the exception of scat cranks. But never used one so not sure. Eagle cast cranks are basically trash.

 

[cudamark]

I'd go with a billet crank myself.

 

[pittsburghracer]

I'd go with a billet crank myself.

A 3000.00 billet crank for 500 horsepower. Lol. Damn I hope you are kidding.

 

[cudamark]

The prices of those must have gone way up since I got mine if that's a true current price. I agree, if $3000 is what you have to spend on one, I'd use a stock forged crank instead for that HP range. IIRC, mine was about $600, but that was several years ago.

 

[brian6pac]

Forged for sure, don't look back. Cheaper to do it right the first time.

 

[toolmanmike]

Light rods, pistons and my steel 273 crank. The pistons would look like Swiss cheese though.

 

[brian6pac]

Light rods, pistons and my steel 273 crank. The pistons would look like Swiss cheese though.

A guy here just got his 340 back from someone in SC, Mopar Specialist built it and he went to put it in and found it had a small register for the converter ? 273 crank ? what years were they smaller

 

[cudamark]

'64-7 had the small register.

 

[toolmanmike]

A guy here just got his 340 back from someone in SC, Mopar Specialist built it and he went to put it in and found it had a small register for the converter ? 273 crank ? what years were they smaller

Probably so. I don't know the year breakdown on the registers without searching. He should ask about balance. They either used a lot of mallory or they found 340 pistons that weigh around 570 grams instead of the 735g that the stockers do.

 

[brian6pac]

Probably so. I don't know the year breakdown on the registers without searching. He should ask about balance. They either used a lot of mallory or they found 340 pistons that weigh around 570 grams instead of the 735g that the stockers do.

That's a big difference, yeah he called the guy and he is building him another motor to exchange it. I don't think I would trust him at this point. If he is a specialist that this guy claims he should have known this wouldn't work, then he told the guy that it was a 4 speed crank and he thought that what he was using, that's why it wont work.

 

[cudamark]

Yeah, on a manual trans it doesn't matter as long as the center hole is machined for a bushing.

 

[pittsburghracer]

The prices of those must have gone way up since I got mine if that's a true current price. I agree, if $3000 is what you have to spend on one, I'd use a stock forged crank instead for that HP range. IIRC, mine was about $600, but that was several years ago.

Are you sure you aren’t thinking that you bought a “forged” crank. Billet cranks like Crower, Calius, Oliver, etc have always been big dollar items. I lucked out and found a used Calias 4.5 stroke big block crank two years ago for 500.00 for a spare and grabbed it. The one in my 572 cost me 2300.00 plus shipping back in 2008.

 

[MOPAROFFICIAL]

. My question is would you feel good with a high-end cast crank like a 900 series scat?

Absolutely.
Or ohio crankshaft.
Nodular iron.
I run one in a 410. Blew the cyl wall out ..meanwhile the crank is perfect.
JMO BUT FORGED IS FOR 600HP+

 

[pittsburghracer]

I sold off a .030 over 340, Scat rods, scat cast crank, Wiseco pistons, rings, bearings, damper, flexplate, etc all new because I was afraid of runnings 9’s with it. Some guy from the east coast made an over 1000 mile road trip for it.

 

[448Scamp]

I would like seasoned opinions on crankshaft material choice for a 450-500 hp 4 speed. Big clutch and 275 drag radials am considering a 3.58 stroke 340 . My question is would you feel good with a high-end cast crank like a 900 series scat or would you just bite the bullet for forged and never look back.

What is a Big clutch? Never heard of that brand before. I’d never use a cast crank. Spend a few extra dollars and get a forged crank.

 

[jimjimjimmy]

i know Ramm built a 697 hp stroker with a scat 9000 that has stood the test of time i run one at 530 hp and spray with a 100 shot over 10 years now pick your poison . both will work fine . there are thousands of 500 plus hp small blocks running the scat 9000 .

 

[furrystump]

Breaking a crank is catastrophic. The difference in price is max $400-$500 maybe less. I run a Scat cast crank and shift at 6300-6400 rpm. It is fine where I’m at, but would be uncomfortable taking the next step I need to go quicker with it. That being going roller cam. Don’t paint yourself into a box.

 

[K.O. SWINGER]

What is a Big clutch? Never heard of that brand before. I’d never use a cast crank. Spend a few extra dollars and get a forged crank.

Big clutch is an old school term for heavy plate pressure. There's a reason factory used forged cranks in there 4 speed cars. Combine a serious clutch and drag radials it can really stress a crankshaft.

 

[Krooser]

My Mopar billet crank was $1800.00 in 1993.

When we didnt know junkyard cast cranks wouldnt work we got at least two seasons of racing in our dirt cars with a SBC 550 hp and those junk cranks.

. Now that we are smarter we get one or two years out of our $1500.00 Callies, Scat, Lunati or similar cranks with 100 more oomph.

Thank God we know better today...

 

[448Scamp]

Big clutch is an old school term for heavy plate pressure. There's a reason factory used forged cranks in there 4 speed cars. Combine a serious clutch and drag radials it can really stress a crankshaft.

Got it. So what is the benefit of a big clutch?

 

[K.O. SWINGER]

Got it. So what is the benefit of a big clutch?

Lack of slippage, I've always ran 340s and on Max output leave around 45,00 to 5000 RPMs that combined with the drag radials will go through a lighter clutch causing it to wear out quickly(slip) a few hard slips and the clutches toast.