If you are running a surge tank based system, the stock, unbaffled tank works excellent when plumbed correctly. There are two things to keep in mind when using this system design.
One, running an EFI rated fuel pump submerged in fuel to cool it is the way they are designed to be run. They can live when mounted outside the tank, and depending on load, they can live a long time, or not.
Two, the fuel pressure in the feed to the surge tank from the stock tank is at or near "0" psi. This low pressure side of the system free flows from the tank, to the surge tank and back to the tank.
This low restriction, low-pressure side of the surge tank system not only reduces the load on the feed fuel pump which reduce their operating temperature(whether its mounted inside or outside the tank); and the high volume of fuel flowing through the low pressure loop to the surge tank cools the pump. Externally mounted pumps reduce the heat transferred to the fuel from their exterior surfaces, and are also slightly air cooled.
Virtually all the air is removed from the lines at the surge tank as the feed and return lines are mounted at the top of the surge tank.
The high pressure fuel pump is submerged in the bottom of the surge tank in cool, virtually air bubble free fuel even when the stock tank is down to just under a gallon of remaining fuel during road course type, full-throttle driving conditions.
There are a few decently baffled or sumped tanks out there, but using a surge tank can make even a stock tank work well for an EFI upgrade. I see a lot of guys spending big money on poorly designed baffled tanks and they still have problems running below half a tank of fuel. Note to self...it's not the tanks fault. It a failure to understand the benefits of using a surge tank.
Another alternative for really high power EFI systems is to use the newer GM modular Cadillac or Corvette fuel tank modules with additional pumps and pick-ups. Vaporworx has done a lot of interesting things with this set-up.
https://www.vaporworx.com/Most modern "Tuner" cars run surge tanks on their high performance turbo motors for the same reason. A good surge tank set-up removes the air during tank slosh or low fuel situations.
