Project NSX: Part 6 – Building The Ultimate Fuel Pump Assembly

Pump Comparison Chart
Reid at SOUNDPERFORMANCE compared the Walbro 416 above with the famous Denso “Supra” Pump, Walbro 255, and the Bosch 044.  As you can see, the Walbro 416 outflows all others by a significant margin, over 100lph more flow at our target 60psi of fuel pressure under boost.

Cut Barb
The first step in building our ultimate fuel pump is to modify the Walbro’s barb.  We had to cut off most of the first barb in order for our new Brown and Miller Racing Solutions O-ring fitting to be able to reach past the second barb so it can clamp down on the shaft.

Brown and Miller Racing Solutions (BMRS) has an arsenal of industry-leading military-grade fittings, hoses, clamps, adapters, electronic wiring, etc…  They supply most of the NASCAR, Indy Car, and IMSA fields as well as their PTFE lines and fittings to most of the top forms of motorsport around the world.  Polytetrafluoroethylene (PTFE) is a synthetic fluorocarbon solid consisting of carbon and fluorine.  The most common use of PTFE is as a non-stick coating for pans and cookware.  The best known brand name of PTFE is “Teflon” which is a registered trademark of DuPont.  PTFE is hydrophobic and has an extremely low coefficient of friction against any solid and is extremely resilient against corrosive chemicals.  This makes it the perfect material to interface with all fluids in a racecar.

BMRS lines
BMRS has a vast array of products in their ProGold line, from convoluted to smooth bore PTFE lines, to Stainless Steel, Polyester, and High Temp Polymer (HTP) braid with sizes ranging from a small -2 to a large -32 radiator line, and every connection and fitting you can imagine.  Their fittings have a constant internal radius with no necked down restrictions or abrupt changes in angle that can increase pressure drop and there are no welded, glued, or brazed joints either.  The entire product line is industry-leading and often copied, but never duplicated.

Almost all of BMRS’ lines are convoluted PTFE hoses which are extremely light, flexible, and compatible with ALL fluids used in racing.  PTFE has been used in motorsport brake lines for many years but BMRS has taken this technology and developed it for applications ranging from vacuum lines, to water, fuel, and oil lines.  Combined with their hose construction, fitting materials, and clamped fittings, BMRS have some of the lightest, strongest, and most versatile lines on the market.  Due to this construction, BMRS lines will not cause gasses to seep through the hose and cause your car and garage to smell like fumes which the old-school cheap ‘hot-rod’ lines and even many modern copies are notorious for.


Here we see this trick BMRS O-ring fitting that is used on many applications including IndyCar.  As the top half of the fitting is tightened, the conical shape under the cap squeezes O-ring down against the flat base, which causes the O-ring to flatten out and squeeze the inner tube which makes for a tight, solid seal.  You can also see the cylindrical back side of the fitting with 4 slight barbs which grab the PTFE line when the outer sleeve is crimped down onto it, ensuring a strong and flawless seal.

Fitting Barb Pic
While this connection is used in IndyCar and probably could hold our 60psi fuel pressure on a straight tube alone, with the lip of the barb intact, this connection will not have any issues until well past 60psi as failure in our connection would only take place if the plastic barb ruptures.

6 comments

    1. Thank you. Contact Brown & Miller Racing Solutions and tell them the dimensions of the shaft and barb of your fuel pump fitting (I can’t remember off-hand) and they will get you the correct part number. The wire bulkhead connector is ATL CFD-504.

  1. Great solution.

    Only issue is wire configuration: fuel vapour will travel up through the wire – wire can never be installed like this; a better solution is to connect each end independently to studs.

  2. What made you decide to keep the factory return hard line? With all the work already done, did you consider making the return line bigger?

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