Which Electric pump to run through a mech pump?

I am running out of ideas on how to make a mechanical fuel pump keep two Holley 600's full at WOT.
I refuse to convert back to a electric pump full time but a helper pump might take care of the issue. I read the thread from June 16 about running an elctric through a mecahnical.
Is there a particular brand that lends itself to this setup? I see Carter has a4600 seies rated at 8 PSI and a 4601 rated at 15 PSI. Would the 15 be too much pressure on a mechanical?

I would only want to use the electric 1% of the time

I always go by the gpm to determine the pump required for a praticular setup. Any electric pump will work in combo with a mechanical that I've ever tried. I'd try calling the pump manufacturer and talk to their tech guys and see how they would suggest hooking it up. Should be able to give line diameter requirements and the what you need to do as far as a return line or just a pressure regulator.

Determine the volume of fuel needed at WOT, then find a pump that can constantly deliver that volume of fuel.

do you know if it is the lack of fuel, from a pressure drop, on a gauge?

.. or is this not pulling secondaries open limiting airflow.. or secondaries opening not pulling fuel to demand not supply..

I'm in the process of rigging a system just like this into my 79 Magnum. I am running a fairly healthy SB.

I am feeding a self regulating 110 GPH Holley mechanical pump(P/N HLY-12-360-11)with a Holley "Blue" electric. I tore out all my factory fuel lines and replaced with 3/8" aluminum to the engine bay.

I have a regulator set at 5 PSI BEFORE the mechanical pump. All I want to do is supply a bit of positive pressure on the mechanical. I felt feeding the mechanical with the full 14 PSI that Holley says the Blue pump is capable of, might damage the diaphragm in the mechanical.

One question I have is, will the mechanical be able to "suck through" the electric in case the electric one fails?

Bad

I know people do it but I wouldn't run an electric through the mechanical pump. I have seen where the electric actually puts too much pressure on the diaphram of the mechanical blow it and filling the pan full of gas while still supplying enough fuel to run on. Needless to say what happens then.

this is with a 5 year old Carter Sreet /Strip pump running through a reg set at 7-1/4 lbs.
It is a 3rd gear pull. The lean spike at 4:14 I "suspect" is a "gulp" of air from the bowls??

I`ve been running a Mallory comp pump ahead of the mechanical for 17 years. It has regualtor and I dial it back to 4-5 PSI before the mechanical pump.
It will pull thru the electric pump if I choose to turn it off, however it runs a lot smoother with both running, and helps a ton with vapor lock and long term storage and start ups..
Car is a stock 440 with Carter Comp. series carb..

Is the Mallory pump, the 110 model?

help me understand why you don't want to run a dedicated electric pump when you are willing to run both?

I would only use the electric when Test an Tunin.

I can put 500 miles on my car in a week and never open the carbs. I do not want to listen to an electric 100% of the time when I only NEED it 1/10% of the time.