Originally Posted by Sunrocket24 (Post 3506671)

My new build engine is 468 with stock bottom end, 088 heads, Isky 270/280 mega, 1.7 roller rockers, Edelbrock intake and 750 marine carb. Made 407hp at 5000rpm and 474ft lbs max torque at 3800rpm on the dyno at Orlandi Performance.

Originally Posted by Sunrocket24 (Post 3506859)

Yep, I thought it would make more. I'm happy with it for now it was my first engine build. The stock 330 decided to eat the number 7 exhaust valve last year. It's got about 12 hours on it now and I'm trying get the right prop on the boat for it before it goes into storage.

Originally Posted by SB (Post 3505197)

The performance boating I/O world can be and usually is very different......

Originally Posted by endeavour32 (Post 3506637)

Car engines and marine engines are completely different animals....I find it VERY hard to believe that your going to be able to build 550 hp in a 454 with peanut port heads that will work in a boat, possible I guess but highly unlikely. There are lots and lots of variables that are MUCH different than an automotive application.

Originally Posted by Itsallgood995 (Post 3506887)

You should have stuck w/ the peanuts :grinser010: Just Joking


It didn't make any more power above 5k? What exhaust? Rev limiter?

Originally Posted by ROTAX454 (Post 3506871)

And if Mr. Orlandi could chime in and give us the details of the dyno session and the equipment he uses------please?

Originally Posted by endeavour32 (Post 3506637)

Car engines and marine engines are completely different animals. I'm assuming vortecpro is the same vortecpro from the chevelle site. When I built my last engine i consulted with many people on the build of my 427 (440 CI) marine engine. Of which one was Chris Straub from the Chevelle site. He said there was NO WAY i could build more than 425 hp out of that engine and have it work in a boat. I ended up letting Bob Mandara spec the entire engine. We ended up with right around 525 hp at 6100 RPMS. This pushed my Formula 242 to 68 MPH. That said I find it VERY hard to believe that your going to be able to build 550 hp in a 454 with peanut port heads that will work in a boat, possible I guess but highly unlikely. There are lots and lots of variables that are MUCH different than an automotive application.

Originally Posted by Vortecpro (Post 3507103)

The 560 HP 236 headed engine sported 9.6 comp with a 108 lobe separation, probably not the best combination in a boat, but I couldnt see a problem with my 9.1 compression 112 lobe seperation 467 that can make as much as 530 HP with dry headers, why wouldnt that work with inconnel valves and the correct head gaskets, please be specific.

Originally Posted by endeavour32 (Post 3507120)

What is the RPM range of the cam? Dry headers are pretty much a no go for most of us, dry to the tip is loud. Full dry is asking for serious trouble, so with that said your cam is going to have to work with a wet exhaust. Your engine is putting out 1.19 hp per cubic inch with really poor heads. I'm running IMO the best 454 head which is the AFR 265 Ovals, 9.9:1 compression and a custom cam, I'm also making 1.19 hp per c.i.. I have better heads, higher compression and a cam from one of the best cam guys in the marine world. I just don't see how you can make the same power per cubic inch. Dynos can vary a lot, unless both engines are dynoed on the same unit we're comparing apples to oranges in my opinion.

Originally Posted by Vortecpro (Post 3507103)

The 560 HP 236 headed engine sported 9.6 comp with a 108 lobe separation, probably not the best combination in a boat, but I couldnt see a problem with my 9.1 compression 112 lobe seperation 467 that can make as much as 530 HP with dry headers, why wouldnt that work with inconnel valves and the correct head gaskets, please be specific.