I went all in with the hype and put an Edelbrock manifold on it. I still have the factory intake somewhere.
Check which Edelbrock intake you have. If it's a single plane, it's a high RPM manifold & will be a dog at low RPM's. Your dad may have gone that route to match the cam he installed back then. For a low end torque application you want a dual plane intake.
Google it for more info. Also, have you dug into the ignition timing any? That might be something to look at, depending on what your dad might've done . Does your distributor have a vacuum advance? Is it hooked hooked up & working off of a manifold vacuum port?
I put a Gen V 454 with a modern Edelbrock dual plane in my C10. I checked with Edelbrock tech dept about which carb I should use on my mildly built 454 & they recommended the carb you have. Just saying that a 750 is not too big for that engine.
The Holley intake Hotrod Linc mentioned had a great reputation back in the day but is no longer made.
