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Old 09-16-2012, 03:48 PM
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You cannot use the Bosch pumps in a dead head configuration.
The need a return line and a bypass style fuel pressure regulator.

A Carter P4601 pump and holley fuel repssure regulaotor would have been a better choice.
1/2" fuel line.

A pair of Carter P4070 pumps thru (two) twin 3/8" fuel lines (1 for each carb) needs no regulator at all.
The pair will feed that motor with room to spare. Just needs fuel filters inline before the pumps and twin fuel pickups in the tank. (will support over 800HP)

The bosch pumps are more for EFI. You need to dynamicaly flow test your fuel system with bypass and return line to ensure it can feed the motor enough at WOT high rpm. Flow test it thru a test orrifice that is equal area to the combined 4 needle seats. Test for working flow volume and pressure thru the orrifice.
4psi flowing fuel pressure is fine.
If the fuel system cannot keep up to motor demand at WOT the supercharged motor will leanout and burndown.
A 600 horsepower motor needs a fuel system that can flow 60 GPH (US) @WOT max power output.
This is the real flow, thru a test orifice, @ the working pressure and supply voltage. not the advertised GPH rating "free flow". Not the same thing.

.5 (1 half) pound per Horsepower per hour. You want 6 to 7psi at idle and not less than 2.5psi at max flow demand WOT/max power.

Last edited by F-BIRD'88; 09-16-2012 at 03:58 PM.
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