Project NSX Pt 6 Title

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

by Billy Johnson

The NSX’s stock 155lph fuel pump reportedly maxes out around 400whp which will not suffice for our turbocharged 500whp+ goal.  We upgrade the factory pump with the new Walbro 416 E85 compatible fuel pump and visit our friends at Brown and Miller Racing Solutions for motorsport-grade alcohol approved fuel lines, fittings, and electrical wiring.  We finish the build by taking our hanger to be PTFE coated by Calico coatings.

In Part 5, with only headers, exhaust, and some intake manifold work, our Project NSX produced an impressive 269whp which equates to ~315bhp from our naturally aspirated 3.0L C30A motor.  With the turbo motor coming together and plans to almost double the power that we've already made, our stock 155lph fuel pump is not going to be up for the challenge.


NSX Fuel CellJust like an open-wheel racecar or purpose built prototype, the NSX’s fuel cell is located low to the ground and between the driver and the engine.  This is in an ideal location for center of gravity, center of mass, and has very little effect on the car’s balance as fuel is used.

While the NSX’s fuel tank is in an ideal location for performance, servicing anything pump related requires dropping the entire fuel cell which is not an easy task.  Since we are not sure if the car will ever run on E85, we decided to build it right the first time and make everything compatible to run on both E85 and Alcohol just in case.


NSX Stock PumpThe stock fuel pump hanger assembly is tall and has a 45* angle on it to correspond to the tall, but narrow fuel tank.  The fuel filter ‘sock’ is a bit ragged and the steel has some buildup on it after two decades of use. 
Stock NSX fuel pump topFuel is pressurized from the pump and is sent up the steel tube to the top of the hanger.  From here, a banjo-fitting takes the fuel from the hanger to the fuel rail.  The white connector sends power through the bulkhead of the hanger top to the fuel pump, and the bent tube on the right is the fuel return line.
Fuel Pump ComparisonHere we see the new Walbro 416 E85 compatible fuel pump next to the stock NSX fuel pump.  The wide base of the Walbro is the same diameter as the entire NSX pump.  This is the difference 20 years makes.
Page 1 of 6 Next Page
Bookmark and Share
Tuesday, September 16, 2014 10:31 PM
Do you have a link to that specific bulkhead connector?
Tuesday, September 16, 2014 11:18 PM
How is the noise with the 416, I know the 044's make tons of noise.
Going flexfuel this winter and walboro 255 is probably not going to cut it.
Wednesday, September 17, 2014 3:36 AM
The wiring bulkhead connector is: ATL CFD-505

I got it through Roush Yates Parts: http://www.roushyatesparts.com/bulkhead-fitting-p/atl-cfd-505.htm

044s are indeed very noisy. The 416 is reportedly half as loud as the 255.

Wednesday, September 17, 2014 7:13 AM
Might add that bulkhead connector to the RX-7 project. Thanks for the details.
Street Surgeon
Street Surgeonlink
Wednesday, September 17, 2014 8:54 AM
Mind sharing what gauge wiring is used with that bulkhead connector?
Wednesday, September 17, 2014 9:29 AM
14awg mil-spec Teflon wire for use in alcohol/E85. 12-14awg is best for the bulkhead connector.
Dusty Duster
Dusty Dusterlink
Wednesday, September 17, 2014 10:41 AM
Wow, I remember back when the Walbro 255 pump was THE pump to have. Now it looks like a chump!
Wednesday, September 17, 2014 3:37 PM
All that bling and you didn't use tbolt clamps instead of hose clamps? For shame ha

But I am seriously jealous :(
Thursday, September 18, 2014 9:09 AM

The O44's are a great pump but they do not last in E85, the Walbro pump used here is a better choice.
Friday, September 19, 2014 12:14 PM
Where did you go to buy that fitting for the fuel pump, the BMRS doesn't have a sale portion. This article is at amazing time, i am putting together the hanger for my 240, and was wonder a good way to connect the pump to AN lines. Awesome post!
Monday, September 22, 2014 4:17 AM
Call BMRS and tell them the diameter of the tube that you want the o-ring fitting to seal on to.
Tuesday, January 19, 2016 8:16 AM
Not all hoses are rated for complete submersion into fuel. Make sure you check on that before you just grab any old fuel line to use inside your fuel tank. Looks like Billy did his homework here, but not all hoses can be used submerged.

The Walbro F90000267 (416LPH) is MUCH quieter than the Bosch 044, it is even substantially quieter than the 255.
Tuesday, January 19, 2016 7:37 PM
"While at BMRS, we stopped by their WIRED department and had the bulky and ugly weatherpack connector cut off"

Seems to be a lot of stuff about the aesthetics in here. Do you honestly care about the appearance and negligable size of a connector that will spend it's life inside of a fuel tank?
Monday, February 01, 2016 1:49 PM
@SM_Clay72 - It's not about aesthetics, but rather doing things RIGHT. It just so happens that doing things right with the best motorsport-grade products happen to look great as well.

Rubber seals do not do well when submersed in alcohol and can swell out of the connector itself. We removed the connector entirely and used MIL-spec wiring designed to be submersed in gasoline and alcohol as well as the BMRS fuel lines. Rubber fuel lines, connector seals, and uncoated metal may run trouble-free for years when using fuel like alocohol or E85, but what the work we have done in this article will ensure we will not run in to any problems regardless of what fuel we use.
Friday, October 13, 2017 6:00 PM
Hi guys
Great site and awesome car!. Im looking to do something similar to what you’ve done here. It looks really neat. Its been a while now since you did the install and im curious.. how did it hold up? Im worried that the o ring fitting wont seal and degrade over time. Has it failed since you installed it? I assume that the or rig material was PTFE or similar ? Can’t be rubber as it would need to be impervious to alcohol am i right ?
Monday, October 16, 2017 5:04 AM
@Aus335iguy - the BMRS O-ring fitting is made of chemical resistant Viton and will not break down with use of gas, e85, or ethanol. It's been used in Indycar and sports cars without issue for decades. We have a lot of confidence in it's long term reliability.
Post Comment Login or register to post a comment.

MotoIQ Proudly Presents Our Partners:

© 2018 MotoIQ.com