8th Generation Honda Civic Forum - View Single Post

***mucter*** · 02-03-2010, 06:24 AM

I recently decided that I'd had enough of being worried about fuel on my car. I simultaneously went about getting a Walbro 255lph HP pump, CT-e FPR crushing tool and Injector Dynamics 1000cc injectors.

Doug@Hondata noticed I was about to install all of this and stopped me before I did the install. He asked me to run a series of tests to see how each mod increased my fuel pressure and the resultant duty cycle at WOT. He sent me his Honda fuel pressure tester and asked me to test each mod with a 3rd gear pull, monitoring the fuel pressure at the tank outlet and the fuel rail.

I have to give a shout out to my buddy Adam for helping get this done. He had to hold the fuel pressure gauge routed through the window of the car. Trying to hold on and look at the resultant pressure while we're hurtling through the dark rainy Oregon weather...LOL

When I started the test, I had the stock fuel pump, stock un-crushed FPR and RC 550cc injectors. We started by measuring the output of the stock fuel pump. Some of the mods showed a variance in pressure from idle to cruise. Of course since the stock system is returnless, there is a dramatic pressure drop under boost. The resultant psi under boost will be signified by "WOT".

Stock fuel pump, stock FPR, RC 550cc Injectors
Duty Cycle - 100% @ 10.1psi/8000rpm

Fuel Pressure
At tank outlet:
- Idle & cruise: 54.5psi
- WOT: 49psi

At fuel rail:
- Idle & cruise: 52psi
- WOT: 43psi

Walbro 255lph HP Fuel Pump, stock FPR, RC 550cc Injectors
Duty Cycle - 98% @ 10.1psi/8000rpm

Fuel Pressure
At tank outlet:
- Idle: 58psi
- Cruise: 56psi
- WOT: 50psi

At fuel rail:
- Idle & Cruise: 56psi
- WOT: 45.5psi

Walbro 255lph HP Fuel Pump, stock FPR, Injector Dynamics 1000cc injectors
Duty Cycle - 62% @ 10.1psi/8000 rpm

Fuel Pressure
At tank outlet:
- Idle & Cruise: 56psi
- WOT: 51psi

At fuel rail:
- Idle: 56psi
- Cruise: 54psi
- WOT: 44psi

Walbro 255lph HP Fuel Pump, CT-e Crushed FPR, Injector Dynamics 1000cc injectors
Duty Cycle - 53% @ 10.7psi/8000 rpm

Fuel Pressure
At tank outlet:
- Idle & Cruise: 72psi
- WOT: 64psi

At fuel rail:
- Idle & Cruise: 70psi
- WOT: 58psi

02-03-2010, 06:24 AM	#92 (permalink)
*mucter* Jay Join Date: May 2006 Posts: 9,088	I recently decided that I'd had enough of being worried about fuel on my car. I simultaneously went about getting a Walbro 255lph HP pump, CT-e FPR crushing tool and Injector Dynamics 1000cc injectors. Doug@Hondata noticed I was about to install all of this and stopped me before I did the install. He asked me to run a series of tests to see how each mod increased my fuel pressure and the resultant duty cycle at WOT. He sent me his Honda fuel pressure tester and asked me to test each mod with a 3rd gear pull, monitoring the fuel pressure at the tank outlet and the fuel rail. I have to give a shout out to my buddy Adam for helping get this done. He had to hold the fuel pressure gauge routed through the window of the car. Trying to hold on and look at the resultant pressure while we're hurtling through the dark rainy Oregon weather...LOL When I started the test, I had the stock fuel pump, stock un-crushed FPR and RC 550cc injectors. We started by measuring the output of the stock fuel pump. Some of the mods showed a variance in pressure from idle to cruise. Of course since the stock system is returnless, there is a dramatic pressure drop under boost. The resultant psi under boost will be signified by "WOT". Stock fuel pump, stock FPR, RC 550cc Injectors Duty Cycle - 100% @ 10.1psi/8000rpm Fuel Pressure At tank outlet: - Idle & cruise: 54.5psi - WOT: 49psi At fuel rail: - Idle & cruise: 52psi - WOT: 43psi Walbro 255lph HP Fuel Pump, stock FPR, RC 550cc Injectors Duty Cycle - 98% @ 10.1psi/8000rpm Fuel Pressure At tank outlet: - Idle: 58psi - Cruise: 56psi - WOT: 50psi At fuel rail: - Idle & Cruise: 56psi - WOT: 45.5psi Walbro 255lph HP Fuel Pump, stock FPR, Injector Dynamics 1000cc injectors Duty Cycle - 62% @ 10.1psi/8000 rpm Fuel Pressure At tank outlet: - Idle & Cruise: 56psi - WOT: 51psi At fuel rail: - Idle: 56psi - Cruise: 54psi - WOT: 44psi Walbro 255lph HP Fuel Pump, CT-e Crushed FPR, Injector Dynamics 1000cc injectors Duty Cycle - 53% @ 10.7psi/8000 rpm Fuel Pressure At tank outlet: - Idle & Cruise: 72psi - WOT: 64psi At fuel rail: - Idle & Cruise: 70psi - WOT: 58psi Last edited by mucter; 02-03-2010 at 06:30 AM.