only for the pros

[unsunghero0]

[img]{SMILIES_PATH}/icon_question.gif[/img]

does anyone know if the base walbro pump (not highpressure version) will be good enough to support 8psi with 290cc/min injectors.

someone has told me that i will have to use the HP version if pressure gets up to 100psi. i've went to a graph and it looks like pressure is only 10gph around 80psi (translaters to around 60lbs/hr), but i'm not sure i'll need that much pressure in trying to make the 290's flow enough for 8psi (around 210hp)

what do you think?

[S.Bretz]

YOu can have injectors stick closed at fuel pressures higher then around 70 psi...plus most injectors don't really have an increase in flow past the 65-70psi range.

[onemeansaturn]

Stock pump is more than adequate for 8psi and 290cc injectors.

Joe

[Anonymous]

Stock pump is more than adequate for 8psi and 290cc injectors.

Joe

sparing it is not a 97sc.

[onemeansaturn]

Why is that Jayson? I also need to add I don't mean that 290cc injectors are big enough for 8 psi or anything because I'm not sure about that.

Joe

[S.Bretz]

28lb/hr at 8psi wouldbe aboutthe max or slighly lean on a 1.9l. If yo have an eco, then go bigger, at least 30lb/hr.

And 97 fuel pump = teh sucks because they just sucked. They go bad all the time. Theyjust can't pump alot and some times take for ever to build pressure up just to start the car.

[onemeansaturn]

Ahhh. That's right. I did read about the 97 dealyos on the tsn tech article a while back.

joe

[TunerFreak]

28lb/hr at 8psi wouldbe aboutthe max or slighly lean on a 1.9l. If yo have an eco, then go bigger, at least 30lb/hr.

And 97 fuel pump = teh sucks because they just sucked. They go bad all the time. Theyjust can't pump alot and some times take for ever to build pressure up just to start the car.

i can tell u that from experience i have to go though that everytiume i start my car

[Jeremy]

My pump has been [img]{SMILIES_PATH}/cool.gif[/img] to me.

[saturnspeed_12]

Stock pump is more than adequate for 8psi and 290cc injectors.

Joe

sparing it is not a 97sc.

hey it wasnt limited to sc only though, and i also found like a tsb that it was spread through 96-98 years. my sl2 pump took a crap on me.

now that pump should do fine. and about the injectors flowing enough, here is some math and no one get mad, its just the math on it...........

(4) 28# injectors=149.2hp capability at 43.5 psi

pressure adjustment from 43.5 to 55=326cc, 31#

(4) 31# injectors=165.2hp capability at 55 psi

both times were run at a brake specific fuel consumption of .60 and injector duty cycle at 80%. NOW REMEMBER IT WAS THE MATH!!! this can be bent to work out. but the problem is, you can just say 8psi will give you 210hp. its better to go a bit bigger so you know your not killing the injectors to work. 210hp the math brought up 35# injectors at 55 psi with bsfc of .60 and injector cycle at 80%.

also whats your tuning in this?

[sl2racer]

i replaced my 97 fuel pump with the walbro because it kept dropping fuel pressure at wide open throttle and under spray. no more problems.

[unsunghero0]

saturnspeed12,

now thats the kind of answer i'm looking for. thank you!

i'm trying to keep the size of the injector big enough to cover the 210hp at 8psi (or so, i know its not exact due to many things)

but,

i'm also trying to keep it small enough so the stock pcm will not have too much trouble idling and off boost or part throttle response.

so, in your best educated guess, what fuel pressure would you say the 290cc/min injectors would need to be taken to to cover my 8psi goal or 210~ hp goal? i won't hold you to it and yes, i understand why you keep saying 'its just the math'.

for 'tuning' believe it or not, i'm going to test the theory that you can't do something like this and get it 'close enough' by using the begi regulator, 290cc/min injectors and the walbro pump. no other tuning is being used.

again, i'm keeping injectors small enough to keep startup and idle okay while using upped fuel pressure to cover the span for the 8psi.

im running the t-too small stock mitsu turbo and smic.

i'll let everyone know how it goes.

[Jeremy]

have lean spool errr I mean good day.

[unsunghero0]

yeah, i'm hoping the begi with the onset of gain will clear up the lean window there from vacuum to boost transition...i'll be fine.

[Jeremy]

spool isnt vacuum to boost. spool is atmo to boost.