I have RC 440's
Walbro 255
B&M FRP
Hondata

With the Hondata I have no need to run more Fuel Pressure then stock if i'm going to stay under 300whp? Right?

SO I can use a stock FPR and Pump?

Thanks.

 

 

With 440cc's you are going to be right at the point of maxing out the injectors at 300whp. Increase your fuel pressure to 50psi, that should take care of it.

 

Under 300. Like 280whp...

I want to know if I can get rid of my fuel pump and FPR and run stock fuel pressure with the 440's?

 

I don't think so.

I ran the stock pump with 450's and ran stock pressure.

Idle = 33 psi
Atmospheric/0 psi = 43 psi (0" vacuum/0 psi boost)
Max Pressure = 51 psi (8 psi of boost with a 1:1 AEM regulator)

I was at roughly 80% duty cycle with my JRSC @ 8 psi, making about 215whp/142wtq.

At about 6500 rpm, the fuel pressure would start to drop. Stock fuel pressure for the 2000 Civic Si is 31-37 psi @ idle and 41-47 @ atmospheric (per Helms).

Sonny

 

Ok, so keep the FPR & Pump.

Thanks Sonny.

 

BTW - The stock regulator is not a true 1:1 regulator. I tried 3 of them and found that they either did not rise under boost (2 of them had this behavior) or they were not 1:1. The 3rd regulator was the only one without the B&M chop-top. It rose 1:1 up to about 5 psi and then it like .7:1 after that.

Ie, at atmospheric pressure (when the boost gauge showed "0 psi/0 vacuum"...this is WOT on an NA car) my fuel pressure would be 43 psi. At 4 psi of boost, the fuel pressure would be 47 psi (a 1:1 rise). At 8 psi of boost, the pressure would be 49 psi (an overall rise rate of .75:1).

Some people have found different with the stock FPR, but those are my personal observations on my own car. For any decent amount of boost, your best option is to go with a true 1:1 FPR like the Aeromotive or AEM.

Sonny

 

hmmm, So at 280whp & 22psi Max you would recommend a AEM or Aeromotive FPR?

Damn, I thought I didn't need one. I also thought this damn B&M would work.

Oh well, see what happened when I do more reaserch. I end up spending more money.

 

Why would you use a stock fuel pump and stock fuel pressure regulator?

If not for anything but the extra insurance that they are tougher parts and are less likely to fail plus KNOWING that you have more than enough fuel pump, it's still worth it even if you don't really need it.

 

I thought stock fuel pressure would be enough for 280whp w/440's

But Sonny cleared it up for me.