Offshore Addiction

Ive got a super V lite motor sitting here,that with a cam and carb change will make those numbers,but its 12:1 and youll need hot fuel.......

carreraboat

does any of these offshore guys use a vacume pump and low tension rings

Tinkerer

You are not going to get 800 HP out of a 540 no mater what parts that are off the shelf and not some one off heads at 10 to 1 compression. Jim V. lives and breaths heads and his own boat has a 540 that dynos at 750 HP at 10 1/2 to 1 with a tunnel ram.

mcollinstn

heads too small.
cam too small.
intake too small.
carb too small.
headers too small.

I agree on the 625hp number with those parts at "boat" rpms (5600).

Droopy

If you put a good light ring pack with .043", .043", 3.0MM or a 1.2MM, 1.5MM, 3.0MM and run a Vac system its an easy 25hp on the dyno. I would personaly run a 1.2MM Steel top, 1.5MM THG second and a 3.0MM std. tension oil. To do this you would need custom pistons but they would be lighter and you would get more power and reliability out of the combination. Im the high performance ring guy for Perfect Circle Piston Rings and I know these combos will make power over the common 502 metric stack, 1/16" stack and the 5/64" stack. Any questions let me know.

PatriYacht

26Scarab, I've read about some of your valvetrain problems. Have you thought about using a bigger, better flowing set of heads? That way you might be able to run a milder cam and still get good flow numbers. You can always sell your existing heads.

26scarab

40Scarab,
A new set of heads is out of the budget. I'm definitly changing the cam. Hopefully in the next few weeks. I plan on getting something that is a lot slower on the ramp speeds.
I'm sure learning a lot on this cam stuff !

Tinker,
What does JimV have for a cam in that 540 ? and how high is he spinning it? It just seems like a lot of CR to make that power.
A friend has 8.25:1cr in his 720hp 565's. I watched him put 87 octane in the night before a poker run

Tinkerer

Is that DYNOED HP on that 565 -- If you want to know more about Jim V.'s motor just ask him - he is a member of OSO. I have known Jim for a lot of years and If he could get more safe HP out of his engine he would already be doing it. If you are going to start messing around with vac pumps and lite rings then you are starting to get exotic parts. If you didn't already know Jim V does heads for a living and I have seen a lot of his work on race boats. My stock heads are some of his work. I have a 92 -34 SCARAB with 502's doing 77 GPS.
And I will be the first to admit that the boat is loaded and is a tank.

PatriYacht

26Scarab, what parts does your friend with the 565's use. I'm going to redo my 540's this winter. His sounds like a killer combo. By the way, I'll have 2 sets of tunnel rams with duel 750s for sale if anyone's interested. Cheep.

26scarab

Tinker,
Yes that is dynoed. (Tylers) And no exotic parts on those motors just a single 1150 Dominator.
I should have rephrased my question. I did not intend to start a pissing match. I was alway's under the impression that in a marine situation the more power you can make using the least amount of CR and rpm's the better. I don't do heads or motors for a living , just trying to learn as much as possible.

40scarab,
He really doesn't have anything out of the ordinary. The heads are old "D" ports , a Brodix intake, and a custom solid roller cam. The "airflow technician" that helped him out is Ron Sharp from Advanced Airflow. He used to do a lot of work for Joey Griffin (Pier57 boats) before the rules changed and i believe thier are a set of his heads on Jeff Hallets "Motorola/Gaffrig" boat.