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

Fitting Barb Hose
With the cap tightened and the O-ring squeezed, this motorsport-grade connection will be far tighter, stronger, and evenly distributed than any hose clamp or other form of attachment out there.
BMRS hose uncrimped
With our Dash-6 ProGold PTFE line and High Temp Polymer (HTP) braid cut to length, our BMRS fittings are ready to have the gold sleeves crimped to complete the hose.  Due to the inner diameter of the Walbro pump outlet and the short distance from the fuel tank to the fuel rail, a Dash-6 line will give us a responsive fuel system that is sized to be able to power a 675hp Indycar, so it should be large enough for our power goals.
Crimp
All of BMRS lines ranging from -2 to -32 are crimped using this machine.  The crimping process ensures a tight and even pressure around the inner cylinder which is not only stronger and more durable, but also prevents any pinched or loose spots which can cause leaks.  Brake lines have been crimped for a long time because it’s a more secure and better seal.  They are also much lighter, which is another reason why every line on a modern racecar is crimped.  This process is lightyears better than the old school way of tightening a bulky and heavy nut to squeeze the line down onto the fitting, although BMRS does offer a line of these reusable “AR” fittings.


It’s unreal how light this line is.  Including the fittings it is much lighter than an equivalent sized straight rubber hose.  Since we are going to be removing the steel hard line that goes from the pump to the bulkhead, this line will yield a relatively substantial weight savings.

Cut top Hanger
With all of the hoses complete, we turned our attention to the hanger itself.  Master fabricator Chris Farrell starts by cutting off the old and brittle factory connector.
Hanger Cut 2
Next he cuts out the back side of the hanger bracket to remove the hard line as well as to give our new BMRS 30-degree fitting enough room to make the bend.
Cut hanger Top
With the back side of the hanger bracket cut off, Chris cut the banjo-fitting off the top of the hanger and torched it to release the flux that held the feed line in place.  Once hot, the center section dropped right out.
Cut Top 2
Here we can see the hard line removed.  Our new braided line is much lighter than this hard line.
Hanger Bore
Next Chris opened up the wiring hole for our new motorsport wiring bulkhead connector.
Nut Cut
Our wiring bulkhead connector was tapped into a large Dash-12 fitting, which is too big for the room we have available.  Since the thread pitch of the chrome bulkhead connector was specialized, Chris whittled down the base fitting into a smaller nut that will fit in the room we have.
Sandblasted
Meanwhile, I took the dirty and tired hanger to the sand blaster to clean it up.
Widdled nut underneath
With the AN fitting base whittled down to a smaller nut, everything fits perfectly.
Hanger Top sandblasted
The new AN bulkhead fitting and motorsport bulkhead wiring connector look clean and purposeful.  The wiring connector is the same one used on most racing fuel cells out there.
Coated Hanger
With everything pre-fit and working, we sent our hanger off to Calico Coatings to have their CT-42 Red PTFE coating applied to prevent corrosion from alcohol or gasoline.  We were stoked at the end result.  A super smooth and clean looking fuel pump hanger covered with a durable, abrasion resistant coating.
Electrical Hanger
We also had our new whittled down aluminum nut sent off to be CT-42 coated as well.  The underside of the bulkhead connector has an O-ring, and BMRS also supplied us with a Viton O-ring for the nut on the underside to ensure a perfect seal.
PTFE Underside
With everything coated we tightened down the electrical bulkhead connector.
Pump wired
While at BMRS, we stopped by their WIRED department and had the bulky and ugly weatherpack connector cut off and extended the line with their aircraft-grade alcohol-proof PTFE wires.  Wade Brown himself soldered the extended leads and wrapped everything in Raychem Ethanol compatible shrink wrap to leave us with a strong and super clean wiring setup with nothing that could get hung up, unplugged, or break while inside the tank.
Pump lined up
With the wires and fuel lines hooked up, we were ready to clamp the pump in place.
PTFE hanger under
The electrical wires are run through the bulkhead connector and the fuel lines are tight and ready to go.
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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.

      Reply

  2. 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.

    Reply

  3. 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?

    Reply

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