Back to Qjet

[Mertz]

I have a 72 3/4 with 350/350 and pull a 5000 lb trailer once or twice a year. I have some trouble getting up a long 7% grade. I am thinking about going back to a Qjet from my Edelbrock 650. I have headers, MSD ignition, 1.52 roller tip rockers and Edelbrock EPS intake. Can I use the adapter to go from Square Bore to Spread Bore or should I change the manifold to get best performance? The carb guy I talked to said I might want to switch the jets and put the secondaries in place of the primaries. He also suggested adding spring loaded needles to help prevent fuel starvation on the hill.