I am running a larger than stock stainless tank I designed and had built by Rick's Tanks a few years ago. It holds just shy of 30 gallons and fits in the stock location. It had used a -12AN tube to suck fuel out of the tank and there are internal baffles to control fuel slosh while driving.

The problem I had was that my fuel pump would create a vortex in the fuel and start sucking air once the tank got below 3/4 full. Its essentially the same effect when you drain your bath tube. This caused the pump to work harder and cavitate. It took me a while to figure out what was going on.

I thought about how to have a street friendly fuel system that would be able to use most of the fuel in the tank without sucking air. Especially during hard launches and cornering. I initially looked at baffled fuel traps like they use in road course cars, and then looked at snowmobile style pick-ups in all four corners. I even thought about using a Cadillac CTSV fuel module, but was unable to find a way to pulse width modulate the set-up to use with my low pressure carbureted motor.

I finally came upon a 2 speed pump from Fuelabs and a pair of Holley Hydramats. I wanted to use a larger single Hydramat, but my tank had a baffle right in the middle of it. I was able to fit two Hydramats of 11" x 11" and a 15" x 15" in my tank, which covered the floor of my fuel tank and a few inches of the front and back walls of the tank.

The fuel pump runs at a low speed until triggered to switch to high speed by a simple open closed switch. I will hook that up to my secondary's with a on/off NO2 style switch. Once the secondary's begin to open, the switch will close and trigger the high speed operation of the pump. I run a full bypass regulator with an -10AN feed and return. The pump I chose flows 160 GPH at around 15 psi.

I sourced a nice Filler Plate set with nut-ring and some 3/4" submersible fuel line from Harmon Racing cells, so that I could cut an opening in my tank and make the modifications. The set-up I choose should be able to supply plenty of fuel with no air intrusion at a very low resistance to the pump.

Here are some pictures of the Hydramat install in my tank. I decided to mount the fuel pump outside the tank for easier access/maintenance.

Silly question but do you have a sump in the tank?

No sump. Those are old school these days.

The hydra mats are amazing. If there is fuel in there, they will collect it

run the return line so it fills the area of the hydro mat.

Yes, The directions from Holley are very specific about this. I just forgot to get a picture of it before I buttoned it up. A 3/4" return comes down next to the pick-up feed, "T"s and drops it an inch above and next to both the mat outlets.