The crower 4.25 crank is over 2000 dollars and they do not appear to have a 1 piece rear main available. the kits I am looking at are around 1300 complete. Yea, I get the crower is probably hands down a better product and I would absolutely consider it if I was building a 1200hp engine. I will be lucky to get to 525, that crank is simply over kill for this application

Callies Compstar is a nice piece about 700 bucks

Am I crazy for wanting to use the scat 9000 crank? I get it is cast but they have a great reputation for not having issues, I personally believe they are stronger than a standard cast crank but maybe i am wrong. If it was any other cast crank I would not use it. I had a discussion with Eddie Young a couple of years ago on them and he said he had a customer running them in a pair of 750hp blower engines with no issues and that I won’t have any issues in my HP range. The callies crank is an option, its 718 but it does add a decent chunk more cash to the build since I lose the package price discount having to piece the parts together, about 700 per side. These engines were supposed to stay 454 mags/460s so this nearly doubles the original budget to gain 29 cubes per engine

A cast crank It's rated for 550-600HP in a vehicle by the manufacturer. In a boat I'd strongly advise against it. I didn't realize you speaking of a cast crank, skimmed thread...

If it was any other cast crank I would agree. The scat 9000 crank is supposed to be good till at least 700hp

no cast crank is good to 700 hp.it,s physics.

4.25" stroke doesn't apply to same 'rules' as a 4.00" stroke. 4.25" has a lot more journal overlap.

Last few who wabted cat 4.25" strokes I warned wished they would have listened.

Bad luck or was my opinion worth something ? :)

Do your homework. Listen to you rown voice after you do due diligence. You are a big boy.

I was once told that I was wasting my time building gm stock cast internal 454s up to 450+ hp. Allot of those folks also argued that I couldn't use a truck long block lol. Allot of folks tell me not to assemble my own engines. Out of all of the marine engines that I built off of that recipe which was a L29 454 gen 6 cast engine, I lost one. That engine failed at 5000rpm by snapping a valve head off the stem, falling into the combustion chamber and shattering the piston. The rod broke through the cylinder wall and bent the rod almost 180 degrees around and the cast crank doing this at 5k was still perfect and went into another engine. Had that valve not failed, I am certain that engine would still be going today. I built another long block to that engine and was back in the water 2 weeks later for less than 1000 bucks, most of that went the the machine shop to assemble my heads in a hurry and that motor is still in my 27' to this day. In that boat, it was either full throttle or idle so it was abused plenty lol

From all research I have seen, on people who actually have used the scat 9000 in lots of race builds and marine applications, the scat cast steel crank will hold fine under 600hp in a marine application. If we were talking a cast crank form the 80s or any aftermarket cast crank besides the 9000 I wouldn't even be talking about this. The 9000 is newer technology in casting and scat seems to have their stuff together on machining them correctly. Do I think forged is batter? Absolutely, do I need it? That's the debate. Its easy to say throw another 1000 bucks a side at these but then I realize I still need drives, transom assemblies, hydraulic helm.... (replacing king cobras) I guess I'm getting frustrated at this point, this is one of those deals where I was thinking hey, 1500 a side to gain 29 cubes seems reasonable cost wise and then like any other performance build, it is going to spiral out of control. I was going to do this build on my 27 so I did a ton or research and then found my 38 so I never built it. I already have 2 perfect forged 454 rotating assemblies sitting in the garage, 2 brand new sets of 454 030 merc pistons, I have all of my heads, valve train, cams that will not be changing so I am going to see maybe 30hp per side which in my big pig of a boat is going to probably only amount to 1-2mph. I am old and lame and usually have 4 kids on the boat so my boat stays at 3000-3500rpm almost all of the time and do short bursts to top speed once in awhile when its just adults hot rodding around. I can probably still see 500hp with theses engines as a 454/460 so I guess there is that. Once these go together, they are what they are and will not be getting anything more done to them, I have too many other projects that need time and money. I think it is time to reevaluate this idea.

hello..REGALMAN4925

MY 2CENTS........
I RECENTLY BUMMED MY 510S TO 547S
I HAVE SCAT CRANK EAGLE RODS JE PISTONS
MY HEAVY BOAT LIKES TORQUE THAT U GET WITH THE ADDED STROKE
IT IS A INTERNALLY BALANCED CRANK JUST AS THE 4.0 CRANK WAS..
THEN OF COURSE MY ENGINE SHOP '' DYNAMIC SPEED'' BALANCED THE ENTIRE ASSEMBLY

AFTER READING YOUR LAST BLOG,,,SOUNDS LIKE YOU MADE UP YOUR MIND..........GOOD LUCK


REMEMBER THERES NO SUBSTITUTE FOR CUBIC INCHES EXCEPT CUBIC DOLLARS..!!!!!!!!!!!!!

Saw it mentioned, I would not put HP in a marine application without one. You can get away with a lot more in Automotive because it comes off a load. Not marine!