As stated above, running an in-tank pump for a carb can successfully be done a variety of ways without much trouble on lower horsepower applications.

Problems arise though when you try to feed higher horsepower motors with the low pressure pumps that are available. You can use a bypass regulator system, but that has issues and added plumbing.

Cavitation and fuel tank slosh are other issues that you have to keep in mind when designing high volume, low pressure systems.

Modern cars all use dead head fuel systems with pulse width modulation controlled by the ECU. These are all relatively high pressure systems though. No one has overcome the issues with trying to control low fuel pressure pumps using pulse width modulation yet.

I'm using a work around using a high volume, low pressure, two speed fuel pump on a bypass regulated system with the Holley Hydramat pick-up to deal with the fuel control issues in the tank.

The fuel volume is controlled with a simple open/closed switch. Openning the secondaries triggers increased volume from the fuel pump, while at cruise on the primaries it operates at a much lower output. This keeps the fuel pump cooler, so it lives longer on the street. I mounted mine outside the tank for easier access, but it could have been mounted inside the tank.

This is the pump I chose. 40402 Pump: 160 GPH @ 15 PSI - RATED UP TO 800HP This 200 GPH free flow rating fuel pump is programmed to deliver the maximum flow with the lowest current draw available. Nothing else like it