Radium Engineering Fuel Hanger Surge Tank (FHST-RA) BMW E90/E91/E92/E93 N54/N55, Walbro GSS342 / AEM 50-1200 - 20-1970

Radium Engineering 20-1970 FHST-RA fuel hanger surge tank for the BMW E90/E91/E92/E93 3-series with N54 or N55 engines. Built for Walbro GSS342 or AEM 50-1200 fuel pumps (pumps not included).

• Installs inside the BMW tank on the side opposite the factory pump and holds one or two high-flow aftermarket pumps
• The OEM pump fills the surge tank, and the surge tank pumps supply the engine. It targets fuel starvation during high lateral G-force driving
• Drop-in OEM replacement with no permanent modifications; E85 compatible
• The surge tank draws fuel from three sources: the OEM lift pump, the fuel pressure regulator (FPR) and an integrated 1-way fill valve
• RA-series regulator with tool-less knob adjustment. Detents give haptic feedback, each adjusting about 1 psi (+/-0.5 psi)
• 360 degree swiveling vacuum reference port with double O-ring seal. Four interchangeable 10-32 vacuum fittings: barbed (3/16 in barb), 3AN male, push-to-connect (for 1/4 in OD tubing) and a vacuum plug
• 8AN ORB feed port with a preinstalled low-profile 8AN male fitting to clear the OEM pump cover
• Verified pumps for 20-1970: Walbro GSS342, AEM 50-1000 and AEM 50-1200
• Anodized aluminum canister and 8AN male outlet fitting; stainless steel hardware; fuel-resistant tubing and wiring (gasoline and ethanol compliant)
• High-current electrical hardware: stainless steel studs with nonconductive acorn nuts, serviceable sealed connections and ETFE-insulated in-tank wiring. Includes one relay, one fuse and wiring for one pump
• Fuel feed kits 20-0475-03/-05 and the 20-0806 FPR block-off kit are sold separately. The 20-0475 feed kits are not compatible with the M3 because of the exhaust system

Included

• Fuel hanger surge tank (partially assembled)
• Hardware for pump installation
• Filter socks
• DIY fuel pump wiring kit (for one pump)
• Electrical parts kit for external wiring

Pumps are not included.

Fitment

Radium also lists compatibility with the E90/E91/E92/E93 M3 tank. The M3 uses a brushless fuel pump, so the installer must devise their own pump-triggering solution, which the instructions do not cover. Not compatible with BMW 1-series (E81/E82/E86/E87).

Resources

• Radium Engineering product page
• Radium installation instructions (PDF)

Contact us if you are unsure of fitment or Size HERE