June 16, 2019, 10:02 AM
Digger660Fuel pressure with belt drive pump
I have a belt drive pump with alky carb and bypass return regulator and want to know if the wide open pressure can be checked other than going down track.
June 16, 2019, 10:59 AM
SP 124XMy belt pump is at full pressure on the chip at 4400
June 17, 2019, 09:05 AM
DragRaceResultsIt's my thought that a return style regulator should keep the pressure the same (approximately) no matter what the RPM. That is as long as the return line is big enough to bleed off the excess fuel required to keep the pressure at the desired setting. That is why most High Volume systems like the Aeromotive states specifically to use a #10 return.
June 17, 2019, 09:35 AM
Woody Bquote:
Originally posted by DragRaceResults:
It's my thought that a return style regulator should keep the pressure the same (approximately) no matter what the RPM. That is as long as the return line is big enough to bleed off the excess fuel required to keep the pressure at the desired setting. That is why most High Volume systems like the Aeromotive states specifically to use a #10 return.
That's true with a constant flow system with an electric pump. A belt drive pumps output increases with rpm, so does pressure. (usually) The poppet (or diaphragm) sets the idle pressure. A jet is used to control (increase) the pressure at higher rpm. This is useful with alky carbs.
June 17, 2019, 09:46 AM
DragRaceResultsThat makes sense. I know ours increases about a pound on the run.
