i need to boost reference my fuel pump diaphram. can anyone give me a description of EXACTLY where the 'weep' hole is to tap a 1/8" pipe thread? thanks

Most pump vents are in the main pump body casting, most have a "loop" or ring of casting material over the hole. the top of the loop must be removed to tap the hole out.
http://www.dutra.org/pictures/engine/fuel-pump-vent.jpg
DD

i'm running a draw-thru so this wont be necessary as the vacuum will help. I was wrong, thanks for the pic though.

Interesting image, Doug. Looks like one of the early '60s high-volume V8 fuel pumps (with dual valves), but with the \6 operating lever. I've thought about this combo but never deeply enough to work out how I'd cut the pressure down from the V8's 8-9 psi down to the \6 operating range of 3-4psi. Care to tell us more about this pump?

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Too many people who were born on third base actually believe they've hit a triple.

This is exactly what it is, an HV Big Block Mopar pump with a SL6 lever swapped-in.
It puts-out 7-8 psi and I use two different regulators to control the fuel pressure.
4 to 5 psi to the Holley 600 carb. and 5 to 6 psi to the NOS system.
This pumps feeds both systems with-out a problem.
It is too much pump for a "carb only" application.

If you're running it in an NA application, why does it have a boost reference?


Does it really supply enough for nitrous? How much gas did you run with it?

I installed the boost ref. fitting when I built the pump but as you pointed out, don't need it at the moment.
It does not take much to tap the hole and install the fitting so it's there if I ever need it.

Currently I have a 100 HP system, I would like to try a 150 HP shot.
I recently added an electric pump back at the tank for extra "insurance" and to prime the engine for faster starts after it has sat for a while.
DD

How long have you run the 100hp shot with just the mechanical pump?

I think I'd like to give it a shot.

Did you run enlarged fuel lines or anything or was it with stock 5/16 fuel line?