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High-pressure fuel pump suggestion for NA 3.1L converting to EFI

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Hi all!

I have a newly built 3.1L NA L28 race engine going into my track car (71' 240z) and am in the process of converting from carbs to EFI ITB's (Jenvey). I have the Haltech Elite 750 ECU and Bosch 347cc (six) injectors ready-to-go.

My fuel system is currently set-up with dual (independently powered/controlled) high-volume, low-pressure Purolator pumps near my fuel cell. Naturally I will need a high-pressure pump mounted in my engine bay. Any suggestions for a universal high-pressure (40-60psi) make/model would be greatly appreciated!

As an OHC non-crossflow motor that was first developed in the 60's, I would be thrilled if I achieve ~300HP crank.

Cam is .565" valve lift, 290 I/E duration @ 0.05"

CR is 10.5:1 at the moment, but will be raised to 12:1 in time.

Rod-ratio has been altered with 490g rods, and forged race pistons with valve pockets.

There are fuel flow estimate calculators you can find online which you can use for this purpose.

A TI Automotive (walbro) 125lph should be fine for typical pump fuel.

If your pump flows significantly more than you require then you end up with excess fuel circulation (bad because of heat) it also overworks the regulator and you may find you cant reduce the base pressure low enough if the regulator isn't up to the task.

Thank you Scott, that is helpful! I prepared for this instance by routing a 5/16" tank return line and Aeromotive FPR with the swappable diaphragm spring.

On my past street turbo cars, I would employ a surge tank in the engine bay. Im debating if I can save the weight this time around given the NA application and dedicated track car (club racing). I plan to swap my in-cab 0-15psi fuel pressure indicator for a high pressure transducer and indicator. I can use that or my dual broad-band O2's (two collectors) as inputs to the ECU for possible engine lean-protection.

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