Yes, dual plane intakes have more torque and power in the low and mid range...
Single plane intakes have strong power in the mid and upper range...
By splitting the intake in half, the vacuum signal is stronger in a dual plane than an open plenum in the single plane (dual planes have less volume so the signal doesn't get 'lost')... Plus single plane intakes typically have shorter runners than a dual plane... Shorter runners work well in high RPM, where longer runners are tuned in better for lower RPM.... The open plenum in the single plane also allows the other cylinders to "steal" some air fuel from the other cylinders while they are not using it which is a benefit for higher RPM...
If you study fluid dynamics which applies to air flow also, for the same area runner, the longer runner is tuned for lower RPM and short runners are tuned for higher RPM... At low RPM there is more time for the charge to get from the carb to the valve... At higher RPM there is not as much time for the charge to travel, so a shorter runner is tuned in...
That's the theory that they used in designing the cross ram for the super stock engines... As the valve opens and closes, it creates a "pulse" in the intake... You want to tune that pulse in so as the valve opens the charge from the carburetor is just arriving at the valve and it has momentum to fill the cylinder just as the valve opens... That is how they were able to achieve 100% volumetric efficiency at 6500 RPM for the super stock Max Wedge engines... It's very difficult to achieve 100% volumetric efficiency in any engine even with today's computer technology to help design them... I(f the valve was not open when the charge pulse arrived, it would interrupt the air flow...
There are some good dual plane intakes for small blocks... I love the LD340 series from Edelbrock, however they are obsolete and pull good money... Another good dual plane intake for the small block is the Wiand Stealth that has a power range from idle to 6800 RPM and is still available new today....
Here's a link to the Holley page for the Wiand Stealth... Holley bought out Wiand and now owns them...
Weiand 8022WND Weiand Stealth™ Intake - Chrysler Small Block V8
Here is the summit racing page for it:
Weiand Stealth Intake Manifolds 8022WND
By splitting the plenum in half like the dual planes do, you get a stronger signal at the carburetor to help pull the air through the carburetor at lower RPM's... Then using a carburetor base gasket with the divider in the center you keep that strong signal all the way to the carb.... I like to use this gasket with the split center and is also 5/16" thick to help insulate the carb from heat and boiling the fuel to prevent vapor lock... The edelbrock gasket even comes with the correct mounting studs and nuts....
Edelbrock Heat Insulator Gasket
Edelbrock Heat Insulator Gaskets 9266
Here's the comparable gasket from Holley, but it doesn't come with the mounting studs and nuts....
Holley 108-18 Base Gasket
Summit racing listing:
Holley Carburetor Base Plate Gaskets 108-18
A dual plane will give you better throttle response in the street RPM range...
