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FE Power Forums => FE Technical Forum => Topic started by: BigBlockFE on June 18, 2015, 11:14:16 PM

Title: scat forged crank vs cast
Post by: BigBlockFE on June 18, 2015, 11:14:16 PM
anyone use a scat forged crank for their engine build, how was it to machine, does scat even make a forged crank for the fe, I know the cast crank is great for street hp levels..
Title: Re: scat forged crank vs cast
Post by: fekbmax on June 19, 2015, 12:33:48 AM
RPM makes a 4340 forged steel crank for the Fe in several different strokes. Keith Craft and others advertise them. Pro power also offers 4340 forged steel cranks to although its not clear what brand they are. Could be a RPM crank also. Both clame there good for 1000 hp +. They both have them listed on ebay now . 750 - 800 $ range. Scat still list the billet cranks. but not sure about availability.  2,000$ +. Crower also will do a fe crank but they may be made to order idk. I'm sure Barry or countless other engine builders here could steer you in the right direction.
Title: Re: scat forged crank vs cast
Post by: fekbmax on June 19, 2015, 12:36:18 AM
Also I have had a couple of the cast steel scat cranks internally balanced and had no issues. Its a decent piece in my opinion. 
Title: Re: scat forged crank vs cast
Post by: fekbmax on June 19, 2015, 12:40:40 AM
Charlie Booze (Booze brothers racing) told me not long ago he had a billet scat crank left that he may sell. I believe it was a 4.250 stroke. .
Title: Re: scat forged crank vs cast
Post by: Barry_R on June 19, 2015, 05:16:02 AM
I'll keep the pricing generic since several of us can provide these...

Scat offers the cast cranks in 3.98, 4.125 and 4.250 for under $600
Scat offers steel cranks in 4.125 and 4.250 for just over $1100
Scat offers "semi-billet" cranks in 3.78 and 3.98 for around $2000
Scat does full billet cranks in any configuration for $2800 and plus

RPM sells steel cranks in 4.125, 4.250 and 4.375
They sell for around $600 but require work before use - assume and end cost around $900

There are billet cranks also available from Moldex, Crower, Bryant, Wynberg all in the $3000 ranges
There are ebay guys selling really cheap stuff that I would be pretty scared to try...risk versus reward
Title: Re: scat forged crank vs cast
Post by: fekbmax on June 19, 2015, 05:31:58 AM
Great info Barry. Besides internal balancing,  what type of work would need to be done to the RPM crank ? If you dont mind sharing.  I been thinking about one of those for a while. Would it be best to just go with the scat version of the forged steel crank instead ?.
Title: Re: scat forged crank vs cast
Post by: blykins on June 19, 2015, 06:46:59 AM
Depends on if you're brand loyal or not.  The RPM is more than likely going to need touch ground or cut .010/.010.  You'll add the price of crank grinding to the price of the crank, but you'll still be cheaper than a steel Scat. 

If you have access to a good crank grinder, the RPM makes a really nice piece. 
Title: Re: scat forged crank vs cast
Post by: BigBlockFE on June 19, 2015, 07:28:31 AM
Is the RPM crank a Ropert Pond Motorsport or is that a completely different brand...
Title: Re: scat forged crank vs cast
Post by: Barry_R on June 19, 2015, 08:52:51 AM
completely different
Title: Re: scat forged crank vs cast
Post by: Bolted to Floor on June 19, 2015, 11:56:29 AM
What is a "semi-billet" crank? I didn't know there is an in-between.
Title: Brent question: "The RPM is more than likely going to need touch ground
Post by: Qikbbstang on June 19, 2015, 10:27:53 PM
 or cut .010/.010. "
Just wondering if the RPM guys can't machine on the money, do you trust them to manufacture a forged steel crank on the money?..............I'm thinking there's got to be an awful lot of ways to screw up a forging that could make for a weaker crank.
Title: Re: scat forged crank vs cast
Post by: BigBlockFE on June 20, 2015, 12:35:55 AM
The builder on here use the cranks all the time RPM, im sure there are some bad ones every now and then but they seem to be fine, the scat cast is strong up to 700hp, not to many FE for street use with that hp...anything more and I would probably spend the money on all top notch parts, Billet...
Title: Re: scat forged crank vs cast
Post by: Barry_R on June 20, 2015, 05:20:40 AM
As I was led to understand, the cranks I referred to as "semi" were done by Scat as a bunch of billets from standard forging material, roughed in, and left unfinished.  Lets them get a 3.78 steel crank without the full 3 grand price.  I think they were done for one of the Cobra builders that prefer or are required to run standard displacement.  Not sure how many still exist.

As for the RPM stuff - I have a bunch of them out running fine.  They seem to run on the high side of dimensions and be rather variable as well.  I have no way of checking metallurgy although I am certain that Scat does.  The Scat part is definitely different.  While both are obviously forgings, the simple fact is that they are in no way comparable to something from Bryant, Crower, or Scat's own billet offering.  But they do seem to be more than adequate for any normal use.
Title: Re: scat forged crank vs cast
Post by: Bolted to Floor on June 20, 2015, 09:16:04 AM
Thanks Barry for the explanation.