I hadn’t given much thought to a crossover issue as I have a single plane intake (Holley SD) and headers. I honestly thought a single plane did not have a crossover.

I have considered that I’ve had a fuel issue however. The truck lost 2-3 tenths last year - doesn’t nose over but it lost numbers everywhere. I sort of chalked it up to needing to freshen the engine up. I probably need to rig up a temporary fuel gauge taped to the window to get a read on what my cruise and WOT pressure is. Lower pressure = lower fuel boiling point.

I do have a timing limiter plate on the distributor from 4secondsflat for more initial timing (20deg if my memory is correct) while limiting total timing. That certainly improved drivability.