340 Steel Crank

[67_Slimer]

I've decided to go the 340 route and am going to go with new aftermarket rods , pistons etc. I'm just curious if anyone currently makes a new standard Steel 3.31" stroke 340 crank or am I just going to have to use the factory steel one? I've been looking but came up empty every time. Thank you

 

[dartindanno]

Eagle has a steel crankshaft

Eagle Specialty Products 103403310 Crankshaft

Pit Stop USA has Crankshafts and Components like Eagle SB Chrysler Cast Steel Crank - 3.310 Stroke at low everyday prices. Be sure to check out our Crankshafts and Components.

pitstopusa.com

 

[67_Slimer]

Eagle has a steel crankshaft

http://[URL]https://pitstopusa.com/products/eagle-sb-chrysler-cast-steel-crank-3-310-stroke

[/URL]

This is so awesome! Thank you so much!!

 

[RustyRatRod]

This is so awesome! Thank you so much!!

Don't pull the trigger. That's a cast crank.

 

[RustyRatRod]

This is so awesome! Thank you so much!!

Why are you convinced that your factory forged crank is somehow inferior?

 

[Dart Frog]

This is the one I use. It will handle whatever you want to throw at it.

 

[CRUZE 418]

Yes, what's wrong with the factory steel crank? My 340 had a 318 steel truck crank in it until I stroked it.

 

[TT5.9mag]

Small Block Chrysler 340 4340 Forged Standard Weight Crankshaft

Another option. That you won’t be able to break.
Edited to add; my apologies that scat crank is only available in 3.58 or 4.000 stroke. No 3.31. Sorry

 

[Hellrats]

Nothing wrong with the Mopar cast crank either. Probably the toughest cast cranks built. I raced them for years and never broke one.

 

[33IMP]

I would check with Molnar or Ohio Crankshaft.
Edit: looks like Ohio only lists a 4" 340 crank.
2nd edit: Molnar doesn't show a 3.31 either.

 

[RustyRatRod]

Nothing wrong with the Mopar cast crank either. Probably the toughest cast cranks built. I raced them for years and never broke one.

Yeah, but the Eagle cast crank the member posted in post #2 were the ones that were bad about breaking at the first crank throw. That's a definite step down from a factory forged crank. Even a step down from a factory cast crank, IMO.

 

[toolmanmike]

I've decided to go the 340 route and am going to go with new aftermarket rods , pistons etc. I'm just curious if anyone currently makes a new standard Steel 3.31" stroke 340 crank or am I just going to have to use the factory steel one? I've been looking but came up empty every time. Thank you

What engine are you replacing and what 340 are you building? Do you have just a block only? A simple wanted ad could find you a 340 crank. Shipping wouldn't be too cheap but you might find one within a short driving distance.

 

[67_Slimer]

What engine are you replacing and what 340 are you building? Do you have just a block only? A simple wanted ad could find you a 340 crank. Shipping wouldn't be too cheap but you might find one within a short driving distance.

I found 2 cranks within 20 minutes of my house but for 200 bucks more , I thought , why not go brand new?

 

[67_Slimer]

Yes, what's wrong with the factory steel crank? My 340 had a 318 steel truck crank in it until I stroked it.

Nothing wrong , was just thinking why not go new , but after seeing prices , I'm thinking I'll just go with a factory steel.

 

[toolmanmike]

I found 2 cranks within 20 minutes of my house but for 200 bucks more , I thought , why not go brand new?

Keep looking. $200 more than the $1100 or $1200 quoted above?

 

[RustyRatRod]

Nothing wrong , was just thinking why not go new , but after seeing prices , I'm thinking I'll just go with a factory steel.

No way would I replace a factory cast OR forged crank with one from China. Wouldn't happen in my world.

 

[toolmanmike]

No way would I replace a factory cast OR forged crank with one from China. Wouldn't happen in my world.

I would run a cast crank before I would do that. The OP's "aftermarket rods and pistons" may net need a forged crank depending on how it's built. A cast crank could handle 400+ horse all day long.

 

[RustyRatRod]

I would run a cast crank before I would do that. The OP's "aftermarket rods and pistons" may net need a forged crank depending on how it's built. A cast crank could handle 400 horse all day long.

And then some!

 

[toolmanmike]

And then some!

May be I'll ad a + sign after the 400 to make it more accurate.

 

[67_Slimer]

I found a forged 340 crank nearby for $250 , I pick it up tomorrow.

 

[toolmanmike]

I found a forged 340 crank nearby for $250 , I pick it up tomorrow.

There you have it. Send it off to the machine shop to be checked and ground and polished as necessary.

 

[RustyRatRod]

I found a forged 340 crank nearby for $250 , I pick it up tomorrow.

I think that's a wise decision! Made in USA!

 

[toolmanmike]

AI says:
AI Overview

A forged 340 Mopar crankshaft is typically capable of handling upwards of 600 horsepower. While a cast crank is generally good up to around 500 horsepower, the forged version offers significantly increased strength and durability, making it suitable for higher-horsepower applications.

 

[67_Slimer]

Thank you to all , now while I have people's attention , any suggestions on .060 over pistons? I'm looking for a very high performance build. Aluminum heads. street strip style car. maybe 11.5/1 ? Also , would the factory rods that came out of my 1971 date coded 340 work for what I need?

 

[Mopar Sam]

Thank you to all , now while I have people's attention , any suggestions on .060 over pistons? I'm looking for a very high performance build. Aluminum heads. street strip style car. maybe 11.5/1 ? Also , would the factory rods that came out of my 1971 date coded 340 work for what I need?

I would only bore to the minimum size that will clean up.