68fastback,
The main difference in a single plane and a dual plane is the path to the cylinder heads, Dual planes are usually a less direct path and therefore are better suited to wide rpm range torque production at lower rpm(under 6500). Single planes are designed to produce maximum power in a smaller rpm range usually at a higher rpm at the expense of some lose of lower end torque.
Unless you have a high compression, large cam, high rpm engine, your usually better off with a dual plane, That's what I'm running. And the higher torque is especially important with a heavier vehicle. Torque is also what you feel when you mash the gas... HP is a function of torque x rpm... But we wont get into that.:read2:
Hope this
Bjkadron
