A Holly is a wonderful thing for performance,,,, sadly it was never designed for economy. Your Edelbrock was origionally a Carter AFB (aluminum four barrel) until Edelbrock bought the patent rights years ago. In 'proper' tune, the Ed should run on par with the Holly. I ran dual quads on my A/MP L-88 '67 Camaro 10.90 ET/127 MPH,,, when the car was new. Jetting and metering rods can be a hassle, but once dialed in the carb works great. Unlike Holly, there is no power valve, so a bog or back fire is of no concern,,, ohhhh,,, your static CR is around 9:1 depending on cumbustion chamber volume. I ran a simulation on the DT Dyno and HP @ 5000 is 250 and TQ @ 4000 is 310 based on your info Peter