I went from a edelbrock single plane to a dual plane performer RPM. I did not notice any gain in rpm on the top end but the RPM manifold had better all around driveability. I turn my engine 5300rpm with the RPM no problem. I think the RPM is best for ALL around performance. I also had a 650 holley on it last summer. Uping that to a 750 marine holley this year. Hope this helps.
Omega