Surge Tank Installation (More-so AN Fitting Connection to OE Fitting)

[M0nk3y]

Hopefully someone has gone down this road prior to me and can help me out.

Boosted Harrop Engine running E85 on 85mm Pulley. I've been having fuel starvation and as thus going to a dedicated surge tank setup to ensure fueling is satisfied on track.

Wanted to go a clean installation, so this is my part list:

20-1073 Fuel Hanger, 12-21 FR-S/BRZ/GT86: http://www.radiumauto.com/Fuel-Pump-...R86-P2108.aspx

20-0933 FST-R: http://www.radiumauto.com/FST-R-Fuel...-FPR-P348.aspx

13-0029 FST Mounting Bracket, Angled Mount: http://www.radiumauto.com/FST-R-Fuel...-FPR-P348.aspx

20-0152 Fuel Pressure Gauge with 6AN Inline Adapter: http://www.radiumauto.com/Universal-...auge-P227.aspx

F90000267 Walbro Electric In-Tank Fuel Pumps F90000267: https://www.summitracing.com/parts/vpn-f90000267


So, intent is going to replace the OEM Basket with the Radium Fuel Hanger. Pretty easy drop in/PnP as far as my understanding. From there, I'm going to throw the supply line out of the fuel hanger to the FST-R. Surge tank has a integrated fuel pressure regulator so that's satisfied since we're going away from a returnless system.

Return line dumps from the FST-R back to the Fuel Hanger (which conveniently has a return line inlet on the top of the unit.

My issue is where my actual new supply line needs to connect up to existing fuel system (and I need to know where the fuel filter resides in OEM form).

I've been tossing up running a completely new fuel supply line to the front of the engine compartment (where we then step down to high pressure/low pressure) and/or if I just simply go from AN to OEM Fitting back at the existing fuel sending unit connection point and call it good.

Anyone run into similar thoughts?

[RedReplicant]

I have more or less the same setup you're talking about doing in my car, but it was done before I bought it. The car made 375whp on E85 with the normal returnless style.

The stock fuel tubes are still in place and it is my understanding that the surge tank exit is plumbed to the stock fuel tube inlet that normally connects to the stock fuel pump outlet.



This is the stock fuel tube, it drops down on the drivers side and supplies two fuel hard lines. The single inlet connects to the fuel pump.

[M0nk3y]

Originally Posted by RedReplicant

I have more or less the same setup you're talking about doing in my car, but it was done before I bought it. The car made 375whp on E85 with the normal returnless style.

The stock fuel tubes are still in place and it is my understanding that the surge tank exit is plumbed to the stock fuel tube inlet that normally connects to the stock fuel pump outlet.



This is the stock fuel tube, it drops down on the drivers side and supplies two fuel hard lines. The single inlet connects to the fuel pump.

I can't find the correct part diagram that shows those 2 connections off the main fuel pump feed. What do those 2 separate lines feed?

My understanding (or what I thought) that DI/PI was done up at the front of the engine.

[RedReplicant]

Originally Posted by M0nk3y

I can't find the correct part diagram that shows those 2 connections off the main fuel pump feed. What do those 2 separate lines feed?

My understanding (or what I thought) that DI/PI was done up at the front of the engine.

There are three lines that travel to the front of the car from the tank, two are fuel and one is evap.

You can see them on the diagram here:
https://www.subarupartsdeal.com/part...=02&pnc=42081C

[M0nk3y]

Originally Posted by RedReplicant

There are three lines that travel to the front of the car from the tank, two are fuel and one is evap.

You can see them on the diagram here:
https://www.subarupartsdeal.com/part...=02&pnc=42081C

Perfect.

You don't happen to know the barb fitting/male piece size that's going into that OE Female side?

I would assume it's 5/16th, something like this should work: https://www.summitracing.com/parts/e...hoCSMwQAvD_BwE

[RedReplicant]

I'm not sure, whomever did mine has it tucked above the tank where I can't see it through the access ports.