[Cliff R]

It really makes no sense to put a mechanical pump in front of a good electric pump as it simply becomes a restriction for it. Electric pumps are "free flow" and mechanical pumps have valves that open/close and obstruct the flow from the electric pump.

I'd add that unless you are using a rear sump, in tank pump or fuel cell running an electric pump in front of the tank will still have limitations as you need to do two things when using an electric pump It needs unrestricted feed and works better if placed BEHIND the tank vs in front of it, at least if you have a pretty fast car. This allow us to use the forward movement of the car to help feed the pump, vs trying to use it when the car leaves hard and all the fuel is pinned up on the bumper!..

I've tried every conceivable combination of tanks, sumps, fuel cells, line sizes and electric/mechanical pumps over the years. For the most part you can get away with a small electric pump in front of the tank feeded an engine mounted mechanical pump with mild to moderate performance improvments. Even so, when you really start hooking up and leaving hard the factory in tank pick-up becomes the stumbling block no how many or the location of the pumps in front of the tank.......FWIW......