It would not be a bad idea to get that stock good crank checked for cracks and make sure it is straight before any machine work is done to it so you do not waste your money on a damaged part. If you use the rods you have they need to be checked for out of round and bent. How many miles on that rebuild?
Not to bash Matt above. But if you look in Campbell's forum, as well as search for Paul Z's progress/crank talk threads you will find that he sent one of those Scat cranks off to a crank shop and had it compared to a stocker with the same treatments done to both. The Scat came back around 25% weeker then a stock treated crank. The Campbell guys have done a few stock crank builds that put out awesome numbers.
Good(key word there) stock cranks have gone 9's, and are holding strong in a lot of 10 second trucks. Its all in the skill of the machine shop to do there job right and the prep when assembling the motor, and last but not least the tune to keep it from blowing up(again).
Are the pistons and rods you speak of out of this motor that broke the crank. Or are these new parts? I hope they are new and not out of that broken motor..
Hardness of the surface does not mean anything about strength. Also if you are comparing a Scat crank to a treated stocker, the stocker will show higher surface hardness, but what is underneath? The Scat (or any) aftermarket crank are a much higher density material and are also a cast steel instead of cast iron
Eveyone can make the judgement for themselves, but my two cents is on the new crank vs. the stocker.........
UPDATE.
Well just for shits and giggles I took both of my cranks (stock and scat) down to Castillo Crankshaft Services. I asked him to Rockwell both and prep, nitrate, and cryo which ever one came back as being stronger.
Low and behold, the Scat crank Rockwelled out at 22 and the stock GM crank Rockwelled out at 30.
Just thought I would tell all of you who were interested in this crank and believed Scats bogus 30% stronger BS. More like 27% weaker, maybe that's what they meant ???
When I called Scat and let them know what I found, I was told a few different things. That we already had forged cranks and that maybe I got a bad one :screwy:
I returned the crank and got my money back...
See ya,
I think he had the Scat crank compared to an untreated stocker.
http://www.syty.net/forums/showthread.php?t=70672
Im not trying to kill anyones business here. I am just posting what I found during my build.
Both of the cranks that were compared were stock untreated. The cranks were checked @ Castillo's Crankshaft Services in La Mirada CA. and his heat treater Accurate Steel Treating http://www.accuratesteeltreating.com/ conducted the rockwell testing of both. Both of these places are "THE" place to go for crank stuff on the west coast.
Joe @ Castillo's stated that the cast Scat stuff that is coming out of China is junk and inferior to the GM cast cranks in the steel that both of them use. Since he does cranks for all of the big name shops I decided to take his word for it.
He also stated that our stock cranks are cast steel and not cast iron and he hand picks the nicer machined cores that he does for Nelson Racing Engines and RPM.
So thats all I know and I was just trying to share my findings with everyone.
As for kick ass motors, Campbell is the place to go and when I buy a daily driver Ty I am going to have them build me a nice street motor, as long as it has a GM casting or better :tup:
See ya,
Sorry man, i think i would have to listen to mark on this one, they are in the business of building top quality street/race engines and they simply would not use a crank if it was ''junk'' they have made 700hp using this crank trouble free and i am sure it will handle
more, the stock block would be the only limiting factor
Matt