b18cTurbo

how much whp would 310 cc make whit hondata systeme at max??

D-SPEED

Giuseppe

[Modified by Giuseppe, 2:04 AM 2/26/2002]

type autox

lots. low 11s no doubt. just make sure you have lots of breathing room for underneath your pistions.

sgT

I would expect 310s to max out at around 225whp.

smoothludey2

if you're gonna shell out for hondata it wouldn't hurt to get bigger injectors....310cc sounds just a bit larger than stock...go for at least 440s or 550s.

2000_Civic_Si

310cc injectors will put you at 300whp, but for the extra $40 for 550cc injectors you could get another 40whp.

Common speak english!

b18cTurbo

wth are you ******** ore what?
im doing my very best to speak english. damn on all of you racism people

Giuseppe

he meant your initial post doesnt make any sense.!!!

what turbo, what trim, what psi..?? what motor..???????
etc etc...we dont know what u have.!?!?!

dustin

No.

b18cTurbo

heres my setup dude
b18c5 engine swaped into civic 2000
greddy turbo
9.1 compression
8 psi for now
vorthec fmu 12.1
my goal is 350 whp (get hondata2b whit 550cc??? )

SEFIxCivic

you normally don't run a rising rate regulator (fmu) when you have a stand alone engine management. dustin is right, you can't make 300 whp on a 1:1 regulator and 310 injectors. also 550's are good for about 400 whp at normal fuel pressure.

InfamousRS

I don't understand that? Most people with just the Drag kit and stock 240cc injectors are makeing more whp than that, arnt they?

SEFIxCivic

that's because they're running rising rate regulators. you can increase the flow of injectors to a certain point by mechanically manipulating the fuel pressure.

InfamousRS

So how many cc are being pumped through the stock 240s then? At lest say .5 bar with a boost dependant fuel pressure regulator.

dustin

Yep. You can increase fuel delivery 3 ways:

1) higher flow injectors
2) higher fuel pressure
3) leave the injectors open longer

Obviously #1 is the best idea, #2 works but it is hard on the injectors & pump and is not too precise, #3 only works a little but honda injectors are pretty much near max duty cycle stock. You get to the point where the injector is basically always open (100% duty cycle) which isn't going to fly.. =P You definately cannot compensate for boost with stock injectors and stock fuel pressure.

Dustin

SEFIxCivic

I think its kind of hard to answer that question, but my best guestimation would first begin by asking how much hp does a gsr makes at 7 psi. that would be somewhere in the 250 whp range. 720's will make about 500 whp, so my guess is that the stock injectors are flowing about 360'cc with the rising rate regulator and 7 psi.

downpipe

I quote BlueShadow (hey thats me)
270cc = 187 HP
310cc = 214 HP
320cc = 220 HP
370cc = 256 HP
400cc = 277 HP
440cc = 304 HP
450cc = 311 HP
500cc = 346 HP
550cc = 380 HP
600cc = 415 HP
650cc = 450 HP
800cc = 554 HP
880cc = 609 HP

If your selecting injectors and say for example your goal is 300 HP don't get the 440cc go with the
next size injector like 550cc so that you have room for future upgrades and so you have a safety
margin. (you don't wan't to max out the injectors capabilities.

here is the calculations:
CC = [(expected BHP x 0.55) / number of injectors] * 10.5
so to figure out the HP limit of a 550cc injector,

550 = [(HP x 0.55) / 4] * 10.5

550 / 10.5 = 52.38
52.38 * 4 = 209.52
209.52 / 0.55 = 380.95 HP

so a 4 550cc injectors will be good for about 380 HP AT 100% DUTY CYCLE
so I'd say about 350-360 HP is a safe number for the 550cc, the extra 20-30 HP gives you room for adjustability.
http://www.preludeonline.com/

something i saved because i knew it would come in handy...

dustin

Well, the reality is that fuel delivery is not linear with those rising rate regulators.

Say you have a 12:1 Vortech FMU, running some inline pump. You would think that 80psi of rail pressure would deliver twice the fuel ast 40psi of rail pressure, but it does not work out that way in the real world.

Say baseline fuel pressure is 40psi. At 7pi boost the Vortech FMU will be trying to add 84psi of fuel pressure to that. Now, there is a stock 1:1 regulator on the fuel rail that is intended to compensate for manifold vacuum(and in our case pressure) to keep fuel delivery independent of motor load. So at 7psi of boost we need to add 7psi to the rail pressure to compensate for 7psi of pressure in the manifold.

40 + 84 + 7 = 131psi. Now, even the Airtex pump that comes with the drag kit says "Max 125psi" on it. I have not seen the pressure/flow graphs for the airtex pump, but I doubt it flows much at all @ 125psi of rail pressure. In all reality it probably barely flows at all. So fuel delivery is going to suffer.

If it were possible for the pump to produce sufficient flow at 131psi, the injectors would probably flow in the neighborhood of 400cc/min. But this is just not going to happen. I would venture to say that they actually flow closer to 330-350cc just by comparison of some values.

Of course dealing with that much pressure seriously puts a strain on the injectors, as it takes more current to open an injector when it has 131psi of rail pressure behind it. More current = more heat, which means your injectors are going to fail at some point. This is why honda says to never use past 60psi rail pressure on stock injectors. I fear that this is a contributing factor as to why people blow motors on FMU setups doing high speed runs. After so long not only is the motor hot and more susceptible to detonation, but the injectors are heating up and cannot open as fast as they can at normal rail pressures... and fuel delivery suffers.

Dustin

dustin

This depends on fuel pressure. I bet those numbers are at 43psi like RC rates their injectors. On disc injectors you can safely and reliably run 55-60psi of fuel pressure if you have the fuel system to support it.

These are of course flywheel numbers.

Dustin

SEFIxCivic

i think that chart is on the conservative side. those hp numbers you're showing are at the crank right? i've done a car that made 400 whp on 550's with the duty cycle at about 85%

downpipe

i'm not sure. i copied it from a post awhile back to have for reference...thought i'd share it here.

Sh4rky

This is a very interesting topic. Thanks to Dustin and Downpipe for clarifying everything! I just learned something new.

b18cTurbo

i have the holley 190 lt hr so whit the 550 whit hondata im looking for what whp max???dustin?