Originally Posted by KAAMA

Smitty/Articf, you and Rookie are speaking about a 454cid engine---right? With an engine the size of a 454cid, then I would greatly expect that a dual-plane intake manifold such as the RPM Air-Gap dual-plane to perform much better over a single plane in most cases, but NOT in every case.

Back when I bought my used 32' Active Thunder, the original owner dumped a ton of money in the engines. They were 454cid bored .030" over to 461cid and the blocks were "bore notched" so as to un-shroud the valves on a smaller BBC cylinder bore size. These 461cid engines had small solid/mechanical roller cams with Merlin cast iron Oval port heads that had 2.19"/1.88" valves with bowl porting and short side radius work and the same Dart 4150 flange intake manifolds that I ended up using on my 565cid engines.

Anyway, those little 454's (461") made about 619hp @5500-5700rpm and this is with Stellings full length tubular headers installed on the engines in the boat---and I rode in that boat that way before I even knew I was going to buy it---and it was a real runner and I am thinking the Stellings tubular dry exhaust system was maybe why it could run well enough to install single plane intakes (Dart) on those engines back during that time

I also tend to believe that the more CID you have with the Big Block Chevy then the less reliant it is for a dual-plane intake manifold---at least that is how I used to think until I read the Prestige Motorsports article by Jeff Honeycutt with all the dyno testing results---really has me second guessing myself about those dual-plane intake manifolds---especially on a 582cid engine where Honeycutt in Test #1 stated:---- "We don't want to spoil it, but it was the highest output of any of the tests"-----= so now I am back to thinking a dual-plane intake may actually work on a 565cid engine turning only 5600rpm and lower marine application engine , especially on a 582" that they were conducting dyno tests on during that time..

I may have to end up laying down the SMACK for the Air-Gap dual-plane and do my own dyno test compared to the Weiand Track Warrior manifold which i have already bought---which in the test by Prestige looks to have a slight edge over even the Victor Jr. as Honeycutt comments in his article in Test #5----"We've got to say that Weiand's Track Warrior single-plane intake manifold was the surprise of the test"---- .These weren't decisions that I was expecting this time around, but the curiosity is really rattling me.

Originally Posted by SB

How about in boat comparison tests ?
Like it sounds Rookie might embark on.
Sometimes the dyno tells one side of the story.

Originally Posted by SB

How about in boat comparison tests ?
Like it sounds Rookie might embark on.
Sometimes the dyno tells one side of the story.