cast crank to forged in 440

72dustervs

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Can a cast crank block be swapped to use a steel crank ? With out to much trouble ? I know balancer an flywheel are different , but are there any other issues , I made this swap in a 340 with great results but never a 440
 

Jadaharabi

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Can a cast crank block be swapped to use a steel crank ? With out to much trouble ? I know balancer an flywheel are different , but are there any other issues , I made this swap in a 340 with great results but never a 440

Yes
 

RustyRatRod

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Yes, but no way would I do it if I already had a cast crank. They can withstand 500 HP in as is condition. With good balance work and good parts and assembly, they can withstand around 600. They are stronger than given credit for.
 

Treblig

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Yes, but no way would I do it if I already had a cast crank. They can withstand 500 HP in as is condition. With good balance work and good parts and assembly, they can withstand around 600. They are stronger than given credit for.
I think I was cast when I was born!!:lol:
 

aaronk785

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I agree with Rusty. Never had a problem with a cast crank at about 500 hp. I've had several people demand they need a steel crank for a 400 to 450hp build. Just plain wasted money. I personally wouldn't be scared to go 550 if magnafluxed.
 

RustyRatRod

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I agree with Rusty. Never had a problem with a cast crank at about 500 hp. I've had several people demand they need a steel crank for a 400 to 450hp build. Just plain wasted money. I personally wouldn't be scared to go 550 if magnafluxed.

Yup. 90% is for bench racin braggin rights.
 

72dustervs

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well I have a steel crank that is an 8 bolt flange an has the pilot hole already for the 4 speed that I have , the cast crank does not have hole drilled for 4 speed , which leads me to my dilemma of the swap , my 440 was rebuilt from a motor home with low mileage , cam was replaced with comp cam , unsure of size but is mild from what I was told , the heads are done but are 4006452 but have access to better heads , and new rings on std pistons and new std bearings on the crank ,,,the 440 will be for street driving
 

Jadaharabi

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Take the crank to a machine shop and have it drilled. You need a flywheel balanced for the external balanced motor too.
452s are good heads.
 

Garrett Ellison

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The eight bolt industrial cranks are longer on the rear flange by about an inch and reverse rotation, you need to compare your eight bolt crank to your six bolt crank for differences.
 

Plymouth 65

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The eight bolt industrial cranks are longer on the rear flange by about an inch and reverse rotation, you need to compare your eight bolt crank to your six bolt crank for differences.

I learn something everyday! Thanks 65'
 

DrCharles

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Another thing to check (if you're not acquainted with the flange distance on sight) is whether the eight holes are threaded or smooth. The old 413 cranks for the cast-iron Torqueflites weren't threaded (the studs were on the converter and stuck through the crank flange).

I fell for this one, many years ago... and tried for years to sell it to someone who wanted it for the correct application. Never found a buyer and finally scrapped it. Too bad, it was a nice beefy crank too.
 

72dustervs

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Can anyone identify this crankshaft p5249207 68875 ,,,these are the only numbers on box it came in other than a date of 04 /25 / 00 , this is the 8 bolt flange crankshaft I have , its new in box still but have no info as it came from someone my brother bought it from and he doesn't remember

440 12.jpg
 
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Garrett Ellison

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Care to check the throws and counterweights for any numbers or stampings? It's probably identical to the crank in the article but going on what I've been finding it may be have come from an aftermarket supplier for MP.
 
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72dustervs

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I'm wondering if that's a date or if that indicates a 4.25 inch stroke with std size main and rod bearings. But unless your planning on huge power, I would probably stay with the cast steel six bolt crank and save this one for your all out build.

Yeah I am not going to use this crank for my application , unsure about 4.25 00 being date or stroke , good question , I may still get a steel crank 6 bolt flange , unsure yet , will need to see about getting the cast crank drilled an have to find a damper for it , I didnt build the 440 that came with my Duster and I like knowing whats inside an need to dive in this one a little deeper and if I have to pull the crank to see about drilling it out , I may buy steel forged crank ,,got a year or so to decide on that part ,,for now I am collecting many parts ,,thanks for all the input
 

RustyRatRod

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well I have a steel crank that is an 8 bolt flange an has the pilot hole already for the 4 speed that I have , the cast crank does not have hole drilled for 4 speed , which leads me to my dilemma of the swap , my 440 was rebuilt from a motor home with low mileage , cam was replaced with comp cam , unsure of size but is mild from what I was told , the heads are done but are 4006452 but have access to better heads , and new rings on std pistons and new std bearings on the crank ,,,the 440 will be for street driving

Be careful with that. Most of those do not have a crankshaft register to locate a flywheel properly.
 

dano

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Ford was quite successful with cast cranks. Like all speed equipment it depends on the use and application.
 

Dartnut

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Cast cranks are fine as long as they pass a magnaflux and straightness test.
Debur them and with some good quality machining and a proper balancing job, they should easily withstand 500 to 600 h.p. as long as you don't rev them to the moon.
As you want to run a 4 speed, get the pilot hole machined to accept a pilot bushing and have it installed and reamed to size.
It shouldn't cost too much extra if you are getting all of your work done at the same place...........
 

aaronk785

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Didn't mp used to have a bearing that pressed into the torque converter pilot hole in the crank. Then you can simply drill the crank oversized for input shaft pilot. No precision required.
 
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