Unfortunately for the single plane the mild 351w combination was. In about 90 of the cases thats a big no good buddy.
Single Plane Intake Vs Dual Plane Manifolds Engine Differences Edelbrock Tutorial Overview
Single plane vs dual plane intake. A single plane intake will flow more air than a dual plane intake for the same engine. A dual plane intake manifold has two separate plenums that each feed only four cylinders while a single plane intake manifold has a single open plenum that feeds all eight cylinders. Do you know the difference between a single and dual plane intake manifold. Single plane manifolds have a single intake opening into the plenum and feeds all 8 cylinders directly. It has a 180 degree firing order hence the dual plane single plane has 90 degree firing order for good lower rpm driving. Does that make it better.
It has an rpm range of 1500 6500 that suits my cam selection perfect. The plenum divider has a cut out right below the carburetor. I was wondering about the effect of an open vs. Edelbrock is here to clear that up and make sure you have the correct manifold for your application and use. Moving on to the single plane edelbrock victor jr. An hvh brodix dual plane along with an hvh brodix sp1 single plane intake.
One thing about this intake is it is not a true dual plane design. I now have 1 open carburetor spacers so the leftright side of intake is now mixed between rightleft just under the carburetor. Each side of the opening feeds four cylinders on a v8 engine. Torque production with the dual plane exceeded 400 lb ft from 3800 rpm to 5100 rpm making for a broad usable torque curve. A dual plane manifold has a split opening in the plenum area directly below the carburetor mounting pad. Divided carburetor spacer on a dual plane intake manifold.
The dual plane is a high velocity piece. Intake the peak horsepower output jumped to 441 horsepower at a slightly higher 6500 rpm but peak torque dropped to 405 lb ft at again higher 5000 rpm. In fact in 90 of the cases a dual plane intake will outperform a single plane. This engine produced 630hp with a single plane intake and 580 with a dual plane. In my case i have a dual plane intake manifold where the intake runners leftright are separated. We called high velocity heads and they supplied a pair of intakes for the test.
Some years ago june 2012 we did a dyno test of a small block mopar 408 see our dyno test 19. The classic intake battle between the racy single plane and the dynamic dual plane usually ends up looking something like this.