Yellow Bullet Forums banner

1 - 20 of 27 Posts

·
Back to the front!
Joined
·
5,449 Posts
Discussion Starter #1
Hey guys,

Building a 408 stroker smallblock mopar using a Scat 9000 series cast crank. Just wondering if the shock loads from the stick will be a problem on the crank. I can't see it being any different than running a brake at launch, but im curious to hear your opinions. Car will be making right at around 500hp at the crank. Possibly nitrous use in the future....my thinking that if anyting goes first, it will be the stock block

what do you guys think?
 

·
Back to the front!
Joined
·
5,449 Posts
Discussion Starter #3
For a few hundred more $ why not just get a Scat 4340?
I know thats what most are going to say, but i honestly can't afford it (600 dollars more:eek:), nor do i think i need it...im just wondering with the stick will it make a difference? I dont think so, since builders would like to blame a failure on the stickshift, but in reality, what do you guys think?

I went with the cast in the first place because ive read alot of good on here about the scat 9000 series cranks
 

·
Registered
Joined
·
2,341 Posts
I have run them with great results in the past. I had one off ground (400 SBC) to 2.00" and sprayed a small shot on it (175hp). Ran mid 6's in the 1/8 NA and high 5's on the nos. I didnt turn it over 7200rpm tho.
 

·
Back to the front!
Joined
·
5,449 Posts
Discussion Starter #6
I have run them with great results in the past. I had one off ground (400 SBC) to 2.00" and sprayed a small shot on it (175hp). Ran mid 6's in the 1/8 NA and high 5's on the nos. I didnt turn it over 7200rpm tho.
this was in a stickshift?
 

·
Super Moderator
Joined
·
35,328 Posts
Scat has good tolerances even on their cheaper cranks.... 5 min's ago just finished measuring a ford crank and it was .0002 front to back, taper, roundness etc... tighter in most cases.
 

·
Back to the front!
Joined
·
5,449 Posts
Discussion Starter #10
Scat has good tolerances even on their cheaper cranks.... 5 min's ago just finished measuring a ford crank and it was .0002 front to back, taper, roundness etc... tighter in most cases.
Chris, how much power have you seen the cast stuff live up to?
 

·
Back to the front!
Joined
·
5,449 Posts
Discussion Starter #11
I have run them with great results in the past. I had one off ground (400 SBC) to 2.00" and sprayed a small shot on it (175hp). Ran mid 6's in the 1/8 NA and high 5's on the nos. I didnt turn it over 7200rpm tho.
ive heard guys say 6000rpm or higher and the cast cranks are toast...seems everyone has different experience with them
 

·
Registered
Joined
·
1,232 Posts
Hey guys,

Building a 408 stroker smallblock mopar using a Scat 9000 series cast crank. Just wondering if the shock loads from the stick will be a problem on the crank. I can't see it being any different than running a brake at launch, but im curious to hear your opinions. Car will be making right at around 500hp at the crank. Possibly nitrous use in the future....my thinking that if anyting goes first, it will be the stock block

what do you guys think?
always build a good foundation, with your combination, I see explosion in your future... put a 4340 steel crank in it.. good luck. Sometimes being cheap will bite you in the end....
 

·
Butch
Joined
·
8,209 Posts
IMO the big thing is clearance and oiling, balance, light parts and tune up being correct

I have ran many cast cranks and forged, the 400 had cast made 530hp leaving at 5500rpm with a trans brake

This was a GM 400 nodular iron
 

·
Super Moderator
Joined
·
35,328 Posts
Can't speak for the Scat cast cranks... but...

MANY, many, many thru the years used the old 400 nodular cranks.... in pretty high hp applications, including the use of nitrous. I knew plenty of folks who had 8 second capable engines, spraying north of 350 to them.... Back in the 80's choices were slim for budget racers.... you wanted 3.75 stroke, you used a 400 crank, and many people rpm'd the engines 7500+... without breakage.

I think a lot of younger folks today don't realize that.... and the older folks today have forgotten it... being spoiled by all these 4340 chinese cranks which for a budget racer can take a ton of power.

Now I'm not suggesting we go back to doing things like that just reminding people how it was, not that long ago.
 

·
Registered
Joined
·
2,341 Posts
I had a 350 bored .060 with forged trw flat tops. Had a solid roller, gutted 300 heads. It had a stock NF crank and stock rods (o rods). It ran 7.70's in the 1/8th NA and 6.60's on a 225 shot (88 mustang gt). I put a big shot plate on it and used the old 300 jetting. Never broke it!! I sprayed 150 in low and cut it off and turned on the 300 in 2nd and high. Never ran it at the track with that set up, but rocked the streets with it. You would think a scat 9000 series would be stronger than the stck NF crank.
 

·
Back to the front!
Joined
·
5,449 Posts
Discussion Starter #17
Can't speak for the Scat cast cranks... but...

MANY, many, many thru the years used the old 400 nodular cranks.... in pretty high hp applications, including the use of nitrous. I knew plenty of folks who had 8 second capable engines, spraying north of 350 to them.... Back in the 80's choices were slim for budget racers.... you wanted 3.75 stroke, you used a 400 crank, and many people rpm'd the engines 7500+... without breakage.

I think a lot of younger folks today don't realize that.... and the older folks today have forgotten it... being spoiled by all these 4340 chinese cranks which for a budget racer can take a ton of power.

Now I'm not suggesting we go back to doing things like that just reminding people how it was, not that long ago.
you make a very good point Chris..
 

·
Registered
Joined
·
906 Posts
In the past I have used a stock chevy 350 cast crank. I left at 6800 and turned it to 7600 thru the lights. I certainly dont reccomend it but it was done. Even with a stick, if your clutch is right-on, your parts will live.
 
1 - 20 of 27 Posts
Top