Process West Anti-Surge Tank for Subaru


I just received the latest Process West Anti-Surge Tank with dual DW300 pumps over the weekend, and I must say this thing is STOUT. There are alternatives that look pretty nice from Radium Engineering, but I wanted a complete plug and play system where I didn’t need to source new wires, hoses, or anything else. The Process West was a tad pricey, but it came complete and ready to install. A HUGE bonus is that this is a surge tank that mounts above the transmission cross-member, so it is not inside the cabin where it can produce extra noise, take up trunk space, or potentially leak inside the cabin bay and cause a potential hazard. Kudos to Process West for making a fairly straightforward product that is robust, well documented, and one that flows like a mother.

Each of the DW300 in-take fuel pumps can flow 300lph, giving me a potential flow capacity of 600lph! Holy shnikes! Some might ask “hey, don’t you already have a Walbro 465 pump”? Yes, I do. It also has a tendency to slip out of the stock Subaru in-tank canister nipple, which causes a pressure leak. So while it can handle the flow for the power I’m making, there was a secondary reason I wanted a surge tank: fuel starvation for extreme g-forces (hard cornering on a track), and drag racing. There were a few times when I did full 1/4 mile pull, and near the top of 4th gear, I could feel some slight hesitations, and it was because the stock Subaru canister would run out of fuel. This only happened when the fuel tank was running on the low side, but a full tank would also add significant weight.

Both problems are now hopefully solved, and I can rest assured that fuel starvation will no longer be a problem. Hopefully the install will be as straight forward as they say!