Factory Ford Forged 4v Crankshaft Question ?

DOHC otto

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Aug 19, 2010

#1

• Aug 19, 2010

• #1

Does anyone know the forging process on factory forged 4v cranks ?

Are they drop forged or twisted forged ?

 

D

darkside03gt

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Feb 19, 2007

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Aug 20, 2010

#2

• Aug 20, 2010

• #2

Contact kellogg they make the cranks for ford

 

DOHC otto

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Aug 20, 2010

#3

• Aug 20, 2010

• #3

Factory Ford Forged 4v Question ?

Does anyone know the forging process on factory forged 4v cranks ?

Are they drop forged or twisted forged ?

 

S

san~man

O-G

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Aug 20, 2010

#4

• Aug 20, 2010

• #4

Please, only 1 thread next time.

 

flstang65

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Dec 6, 2007

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Aug 20, 2010

#5

• Aug 20, 2010

• #5

What is the twisted forging process?

 

DOHC otto

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Aug 20, 2010

#6

• Aug 20, 2010

• #6

It has to do with the forging dies if they're single plane or two plane.

Some people say "twist forged cranks" are weaker because they are done with a single plane die and to index the crank throws at 90 degrees, the raw forging is twisted to offset the journals in two planes to create the final raw crank blank which is said to create internal stresses in the forging, as well as an poor grain flow in the metal.

Drop forged cranks are done with two plane dies and need no twisting to index, so when the are dies separated it "drop"s out a ready raw crank blank needing no twisting meaning improved grain flow in the steel and no stresses from the twisting.

However the best is billet forged cranks, meaning machined out of a billet of forged steel, way more expensive tho and I don't see Ford sending billet cranks out in factory cars.

So it has to be drop forged or twisted anybody know ?

 

trinity_gt

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Aug 20, 2010

#7

• Aug 20, 2010

• #7

I think Kellogg was/is the forged crank supplier to Ford and I believe they used twist-forging.

 

DOHC otto

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Aug 20, 2010

#8

• Aug 20, 2010

• #8

trinity_gt said:

I think Kellogg was/is the forged crank supplier to Ford and I believe they used twist-forging.

Click to expand...

Thanks man, I'll call them monday and ask for sure. I didn't see where the other guy posted it when they moved my thread.

 

trinity_gt

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#9

• Aug 20, 2010

• #9

Why's it so important?

 

DOHC otto

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Aug 20, 2010

#10

• Aug 20, 2010

• #10

I was told twist don't respond well to boosted setups, I was about to start my short block and I was going to use the factory crank if I could. If its twist then I'll just order an entire new forged rotating assembly.

 

B

bdcardinal

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Jun 10, 2003

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Aug 20, 2010

#11

• Aug 20, 2010

• #11

DOHC otto said:

I was told twist don't respond well to boosted setups, I was about to start my short block and I was going to use the factory crank if I could. If its twist then I'll just order an entire new forged rotating assembly.

Click to expand...

most of the rotating assemblies with forged cranks you see on the market for mod motors are actually Kellogg made factory cranks.

 

trinity_gt

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Aug 21, 2010

#12

• Aug 21, 2010

• #12

DOHC otto said:

I was told twist don't respond well to boosted setups, I was about to start my short block and I was going to use the factory crank if I could. If its twist then I'll just order an entire new forged rotating assembly.

Click to expand...

The factory Cobra crank is a pretty stout piece easily capable of withstanding a thousand or more HP. And remember, the 2003-04 Cobra was factory "boosted" and responds very well to mammoth twin-screw blowers upping the power to insane levels with no internal reciprocating assembly upgrades at all.

Just how much power are you planning to make? Is this a daily-driver, street/strip, race only or ... engine?

If you're going to be making power that you believe will tax a factory steel forged crank, you're probably going to be looking at every aspect of the rest of the drivetrain, the suspension, the chassis etc too...

 

DOHC otto

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Aug 21, 2010

#13

• Aug 21, 2010

• #13

I'm hoping to make around 650 crank, 550rwhp with a KB 2.6 . My concern was I would build it for that and then want more power using nitrous or turbo on top and have to take it back apart to put a better crank in it to handle the thousand or so hp.

I have the rest of the drivetrain planned out to handle the upgrades.

 

Mustang92

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Jun 6, 2001

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Aug 21, 2010

#14

• Aug 21, 2010

• #14

There have been plenty of guys making 1000RWHP on the stock Cobra crank with no problems so I don't think you have much to worry about.

 

DOHC otto

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Oct 10, 2007

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Rock Island, TN

Aug 27, 2010

#15

• Aug 27, 2010

• #15

Slow on calling Kellogg but I finally did. They are twist to answer the thread, I'm still going to use it with my teksid and forged rods and pistons I'd say the bottom end is gonna pretty much bullet proof. If I don't screw it up putting it all together lol.

 

twogts4us

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Aug 27, 2010

#16

• Aug 27, 2010

• #16

A Cobra crank won't be the point of failure...