Dave,
I've used the performer cam and intake, with a quadajet. Was ok. Maybe because of the carb. Was cheating in a total stocker race car.
But, the Comp Cam Xtreme 4X4 in the same setup livened my 350 up..447"/.462" 254/262 degrees. 1000-5200. Liked it so much I'm gonna put it in the 57. Just a hint of lope. But if youre worried about mileage, I don't think you want lope anyway.