i have 440 cc injectors and i need to know about how much boost can i run on these, up till about 80%-85% duty cycle........... i need some kind of idea so i don't waste dyno time TIA

 

HP Injectors at 40 psi fuel pressure
170 240
280 440
350 550
460 720

at about 80% duty cycle

from hondat.com

 

is this whp?

 

I believe it is wheel hp.

 

yeah, I think so

 

where did you find that at hondata.com?........ i tried looking with no luck

 

http://www.hondata.com/techfuelpump.html

 

I think the key word is 40psi..

art

 

thanx for the link........... Art what do you mean by this?

 

I belive what Art means, is that those whp #'s were obtained with only 40psi of fuel pressure. The pressure can easily be increased to 45-50psi at WOT, thereby spraying more fuel per cycle and thus creating more power with the addition of more air.

 

If you look at the graph, you will see that is supports that hp levels at 40psi. Anything over that then the pump starts to loose its flowing capabilities.

 

Is that a stock Si pump Art?

 

yes it is...Im too sick right now to even look up the walbro specs..

art

 

hey Art, nice avatar!

My 440cc are maxed out at 55psi fuel press. Does that mean I have wy more than 280whp or what?!?!?! I have a JR fuel pump (Walbro I think), perfect a/f ratio and car runs like a champ.

 

if you get something like a vortech fmu doesnt that have the ability to raise your static fuel pressure way over 50 psi? I hear people talking about 80psi and more in some threads. if the stock injectors can handle 170whp at just 40psi wouldnt that mean that if you make under 200whp you dont really need to upgrade? its just a safety precaution right? im a slow learned so if i misunderstood something let me know in a kind manner.

 

The higher the pressure, the more your forcing the injector to stay opem, the high the duty %.. things can get a little dangerous for injectors when they reach 95%+ duty cycle, that's why it's safer to switch to a larger injector

 

ok what im trying to figure out is on RC webiste the flow numbers are in 2 different section so say 440 injectore are saturadted style

but 550 injectors are peak hold, im trying to find out what hondas are to start with
(i had originaly heard they are saturdated) and what people use when upgrading, i have 440 saturated but i already know i have ot get larger ones, so im trying to find out if 550 are the way or is the peak hold going to cause a problem......

 

Understand that fuel delivery increases with the square of fuel pressure...

That is... if you are currently running 40psi and want to double fuel delivery, you will need 160psi of rail pressure (yeah right heh)

Dustin

 

The pump that Hondata tested was the stock fuel pump from my 2000 Civic Si. Here is a graph that compares it to the various Walbros out there:



Sonny

 

if you read the hondata web page, the horsepower figures stated are flywheel, NOT wheel

I maxed out my 440cc injectors on my civic si & stock pump at 240whp... this was with peak 85% duty cycle and 60psi of fuel pressure.

-Xerxes

 

40psi^2=1600 not 160 art....just to help, not being a smart ***

 

I didn't say that fuel pressure squared, I said it varies with the square...

In the same sense stopping distance at speed varies with the square of speed... stopping distance from 90mph is 4 times that of the stopping distance at 45mph.

 

well you know..you could just go 720cc w/ your sleeved built badass 1.7 and stop pretending your a big dog and be a big dog in that teal monster, or you can drop some 440's in there and you can tell me how my gunmetal n1 looks!!

you know i'm just playing see you on the street tom!!!

 

ugh, that is *not* what i want to hear! i just ordered some 440s for my jrsc h22. i'm expecting around 240whp at 9psi of boost. i imagine the drivetrain losses are greater in a prelude than an si, so it looks like i'm going to be right on the *$*#($ edge again!

 

at 60psi, we have seen about 325-340whp before we hit 95% duty.
So I wouldnt go far past 300 with 440s.