FST, Fuel Surge Tank, Single Pump.
A fuel surge tank (FST) is designed to prevent starvation to the engine on vehicles with inadequate fuel tank baffling. The surge tank also provides a quick and easy way to upgade any standard fuel system without the need to modify the stock fuel tank or pump. It is also an excellent fueling solution for vehicles installing large fuel demand power upgrades such as forced induction.
HOW A FST WORKS
The volume of fuel inside the surge tank acts as a buffer to always keep the FST pump supplied with fuel. This volume is maintained by the main fuel tank's pump as well as the fuel returning from the fuel pressure regulator. Excess fuel in the surge tank is returned back to the vehicle's main fuel tank.
HIGH VOLUME FUEL SURGE TANK
Radium Engineering 20-0081 high volume fuel surge tank (HVFST) was designed for users that already have a secondary external fuel pump. It is ideal for high flow external fuel pumps requiring a large reservoir and feed line. It features a large 2.21L (0.58 gallon) canister and a 5/8" (10AN) single pick-up tube, as shown below.

A "lift pump" is required to supply fuel to the HVFST. Excess fuel is then routed back to the main tank (or fuel cell). The pump feeding the engine, draws fuel from the surge tank, with excess returning from the fuel pressure regulator back to the surge tank.
The 3 black ports are used for fuel entering and exiting the surge tank. These ports are tapped to 3/4-16 (8AN ORB) and three -6AN male adapter fittings are provided. However, if larger fittings are required, they can be purchased separately

Radium does not recommend mounting this surge tank horizontally, as the pick-up may be prone to drawing in air pockets.
Included
- Extruded and Machined 6061 Aluminum Canister
- Removeable O-Ring Sealed Billet 6061 Aluminum Caps Anodized and Laser Engraved
- Stainless Steel Hardware
- Lifetime Warranty on all Radium components