Inboard exhaust configuration

[Outrageous]

Thanks Miles,

looking back at some of your posts makes me feel a lot better about my project. Thanks for the info. Do you have any performance numbers with the Vortec installed in the boat. GPH or MPH #s? I have the close to the same setup going in my project. What do you run for D & P on the prop?

[Outrageous]

I like the looks of the height on those dry joint risers in the pic as well. Have you run it with that setup. Why did you choose dry over the earlier style?

[aldo]

No extensions on mine- 351 Ford, or later 350 GM. Just the rubber flapper. Boat spent plenty of time at Montauk and seas from every direction.
New owner still on eastern Long Island. Good luck with your project.

[Miles Offshore]

Just waiting for the crane to come set the vortec in the boat hopefully in the next few days. Ran it in the garage today and it sounds really good. I am told that the main advantage of the dry stacks is that if there is a water leak it will leak to the outside of the manifold/riser joints and not to the exhaust like the old style do. Meaning water wont leak back into your cylinders and major or catastrophic damage. The best i can explain it and it makes sense to me and worth the extra money. So i dont have any numbers yet but the 260 hp previous motor i had i was cruise @20-22 knots @3200 rpm and 9.5 to 11 gph. Running a 16X14 wheel. Hoping i can achieve 25 knots at about the same rpms and fuel burn with the extra 60 hp but we will see lol.

[Outrageous]

Originally Posted by aldo

No extensions on mine- 351 Ford, or later 350 GM. Just the rubber flapper. Boat spent plenty of time at Montauk and seas from every direction.
New owner still on eastern Long Island. Good luck with your project.

Montauk, Block and beyond is where I am headed with the race & gut as back yard. Glad to hear some experience with local water coming at you from all angles. I feel better knowing that I will have a setup that will get me back to the dock under its own power without water backing up into the engine.

[Outrageous]

Originally Posted by Miles Offshore

Just waiting for the crane to come set the vortec in the boat hopefully in the next few days. Ran it in the garage today and it sounds really good. I am told that the main advantage of the dry stacks is that if there is a water leak it will leak to the outside of the manifold/riser joints and not to the exhaust like the old style do. Meaning water wont leak back into your cylinders and major or catastrophic damage. The best i can explain it and it makes sense to me and worth the extra money. So i dont have any numbers yet but the 260 hp previous motor i had i was cruise @20-22 knots @3200 rpm and 9.5 to 11 gph. Running a 16X14 wheel. Hoping i can achieve 25 knots at about the same rpms and fuel burn with the extra 60 hp but we will see lol.

Seems reasonable to me. 60 extra HP should be noticeable and provide the increases that you are hoping to achieve. The Vortecs are defiantly more efficient than their predecessors. Agree on the dry stack theory as well especially with raw water cooled risers. Good luck and keep posted on the outcome.

[Miles Offshore]

Will do, thanks and good luck to you as well. Mines been undergoing a 2 year long overhaul and im now starting to get excited about getting her back in the water.