The biggest concern, as far as pressure goes, would be a value so great that it would overcome the float's ability to keep the needle valve shut... Since the fuel in the bowl is
not normally "pressurized" (except maybe through thermal expansion of the fuel, even then the fuel would likely vaporize or escape through the bowl vent) I doubt that it would cause any issue with the power enrichment circuit... Of course, a high float level is another matter... if the fuel pressure is so great that the float can't keep the valve shut, then obviously, that's bad... According to the service manual (available on this forum - very cool
) the average psi range for the bigblock is 6 psi - the book actually says "pounds" but I assume that "psi" is what's inferred... I would guess that for general street performance, and an occasional visit to the track, that anything in that range would be acceptable... This may seem like another thread hijack, but fuel pressure, as well as fuel temp, are two things that can negatively affect the enjoyment of these cars. Especially with todays crappy gas.... A carb insulator and constant fuel delivery to the carb, are two key areas that yield big improvements.
