I have a new 468 with 088 square port heads and 10.5 to 1 compression. I got the motor with 2 intakes the first is on the motor now and its a victor 454-r single plane. The second is a dart single plane OVAL PORT.I looked at darts website and thet reccoment oval port manifolds on square port heads to pick up torque.
I think I am in need of more torque due to the bravo outdrives need to keep my rpms down.
Would you use either of these manifolds or sell them both and get a dual plane square port manifold???
I dont have cam specs yet but rmbuilder will be cutting a cam for it soon, but I will be running a 850 Barry Grant demon carn I just picked up here in the swap shop.

You don't say what boat this is going in. If its a heavier, family type sport boat...I'd sell them both and buy an Edelbrock RPM Air Gap intake sir.

If Bob (RMBUILDER) is doing your cam, ask him.

It also depends on how many RPMS you are going to turn this high compression engine.

I would go with the Oval Dart.

Torque kills drives not RPM.

I would say neither...the victor puts the RPM range to high, I would rather see a performer air gap if on a heavier boat or the dart square port if a lighter and more H/P style boat...I have seen people do the oval on the rect heads, but they did a LOT of blending the ports to get it to work good...

I've looked at doing a similar adaptation with a Brodix HV Oval single plane. When I put it on the head the ports didn't line up vertically. For a motor that small and stock heads, I would definitely go with the RPM Air Gap. I have a 524 with AFR 305's ported and a pretty hefty hydraulic roller and I am considering changing my Brodix HV to the Air Gap.

Over and over test after test the air gap wins. After a certain motor size, like a 540, it starts to lose but not by much. It's a great all around intake and is not expensive. It's become the bench test for other intakes. If I didnt run a 598 I would have one.

I'd run the Victor.

I'd be sure to run some REALLY good fuel in a 10.5:1 Iron headed marine engine. I'd probably wanna keep water temp as cool as possible, jetting spot on, and conservative with the timing. Otherwise, it really wont matter which intake you run, because neither will perform well if the pistons have quarter size holes in them....