Yes, the Street Dominator is better than the stock 2 barrel intake and an improvement over the factory cast iron 4 barrel like you would find on a 352 Galaxie, what I'm saying is if you're swap meeting shopping and have multiple choices for the used aftermarket intakes that are for sale, I'd spend the couple extra bucks for a dual plane over an open plenum. Trying to balance being budget friendly and getting improved performance for your purpose (weekend toy, cruising, towing, etc) along with making it look "hotrod cool" under the hood is all part of the process.

 

Holley and Edelbrock both produced similar single plane intakes around that time with similar features. If you look at the intakes they are designed with a very small amount of plenum volume, about as small as it could possibly be made. Also the cross sectional area of the intake runners is also really small as are the entrances and exits. This is all done for a reason, carburetor signal.

As everyone knows with a dual plane intake the carburetor is split in half with each cylinder only able to "see" 1/2 of the carburetor. As the engine runs the pulses go back and forth from one side to the other and this gives the carburetor a lot of signal to work with especially at low speeds. This tends to make the carburetor appear to be about 20-40% smaller than it would on a single plane. The single plane doesn't do this, each cylinder can pull from all four of the carburetor venturies on every intake cycle. This tends to give each venturi less signal to work with which may or may not cause a significant metering problem at a given engine speed.

In order for the dual plane to work in a 180 degrees fashion the runners have to be built with more curves and compromises when it comes to air flow. They can be good but generally they are not as good as the more direct approach of the single plane.

At first it would seem that the 180 design would be the best for peak torque and low speed operation and while that's possible it may or may not significantly out perform the single plane especially when it comes to peak torque numbers. Sometimes single plane intakes can be worse about exhaust contamination at certain speeds because there are always cylinders that interact with one on overlap while the other one is into the major part of the intake stroke. This doesn't really happen on a dual plane.

Another aspect that is weird about a dual plane is that at certain speeds they can tend to resonate at a frequency that somewhat corresponds to the total length of the runners of each 1/2 of the intake rather than the length of just one runner as on the single plane. This can make the dual plane act as though it has really long tuned runners which can sometimes give a good boost/cylinder fill at surprisingly low RPM if the cam timing is correct.

You might want to try one and then the other to see what's best.

 

A friend of mine at that time picked it up at the Pomona Swap Meet for $20-$30 bucks as I remember it back in '97. I wasn't going to complain. I had yanked a stock 4bbl off at pick a part and had been using that over the stock 2bbl. That was before broke an exhaust valve on the freeway.I blocked of the exhaust crossover and ditched the baffle.As we all know intakes for this motor aren't cheap. Even back then they weren't. So this was a good find. I'll tell you what with the cam, headers and intake the mid range to high power on this engine is excellent. At 65 mph I get on it 1/2-3/4 pedal the secondaries open and she moves out pulling hard.