Injector sizes

[stevepudney]

I know this has been covered before but what were the ballpark power thresholds of the various injector sizes

444cc
555cc
600cc
700cc
1000cc

 

[antilag]

i think its impossible to say cos gingas were maxing out at about 340hp i believe so he went for the 700's were as my cars around the power and the standards are fine i still think 700's are the way to go enless your going for serious power

 

[Anonymous]

I know this has been covered before but what were the ballpark power thresholds of the various injector sizes

444cc
555cc
600cc
700cc
1000cc

number of injectors times flow rate divided by 7 = power at 85% duty 8)

 

[stevepudney]

number of injectors times flow rate divided by 7 = power at 85% duty

That can't be right :?:

444 x 4 divided by 7 = 253
555 x 4 divided by 7 = 317
600 x 4 divided by 7 = 400

My car runs @ 1.2bar on standard injectors with bigger tubby and I'm getting about 320

 

[Anonymous]

number of injectors times flow rate divided by 7 = power at 85% duty

That can't be right :?:

444 x 4 divided by 7 = 253
555 x 4 divided by 7 = 317
600 x 4 divided by 7 = 400

My car runs @ 1.2bar on standard injectors with bigger tubby and I'm getting 320

http://www.sdsefi.com/tech.html
i can assure you the formula is correct.poss you are maxing the injectors,not a good idea,or maybe the rolling road is not accurate :shock: :shock:
or you`ve upped the fuel press,also not a great idea.

 

[Odin]

Bruce I think your speaking out your b*m again, my car made 311bhp
on powerstation's rollers with standard injectors :roll: .

 

[stevepudney]

I have standard 444cc injectors running no more than 85% duty, standard ecu, my car got 318bhp at well lane. Car was previouly mapped and set up by Ian at Hiteq and according to him was still running slightly rich topend. No I don't have a fuel Pressure Reg all I have is a Walbro pump.

??????????????

 

[Sirnixalot]

Remember that the stock fuel pressur regulator will raise fuel pressure in a 1:1 ratio with the boost. For every psi of boost above ambient pressure the FPR will add 1 psi of fuel pressure.

If you are running 14psi of boost, your fuel pressure at WOT (wide open throttle) will be 43.5 + 14psi = 57.5psi. This is why you should not raise your base WOT fuel pressure above 4 bar. @ 4bar base fuel pressure and 14psi you will be running 58psi + 14psi = 72psi of fuel pressure @ WOT. This is why its important to find the right sized injector. I garuntee any stock rubber hose will be a bit stressed at this pressure and your fuel pump will be hard pressed to keep that pressure. Also your injectors may stick because the valve cant over come that high a fuel pressure.

444cc @ 3bar @ 85% @ 0.5BSFC = 287bhp
444cc @ 3bar @ 100% @ 0.5BSFC = 338bhp

555cc @ 3bar @ 85% @ 0.5BSFC = 359bhp
555cc @ 3bar @ 100% @ 0.5BSFC = 422bhp

600cc @ 3bar @ 85% @ 0.5BSFC = 388bhp
600cc @ 3bar @ 85% @ 0.5BSFC = 457bhp

700cc @ 3bar @ 85% @ 0.5BSFC = 453bhp
700cc @ 3bar @ 100% @ 0.5BSFC = 533bhp

1000cc @ 3bar @ 85% @ 0.5BSFC = 647bhp
1000cc @ 3bar @ 100% @ 0.5BSFC = 761bhp

DO NOT RAISE BASE WOT FUEL PRESSURE PAST 4BAR

444cc @ 4bar (513cc) @ 85% @ 0.5BSFC = 332bhp
444cc @ 4bar (513cc) @ 100% @ 0.5BSFC = 390bhp

555cc @ 4bar (642cc) @ 85% @ 0.5BSFC = 415bhp
555cc @ 4bar (642cc) @ 100% @ 0.5BSFC = 489bhp

600cc @ 4bar (694cc) @ 85% @ 0.5BSFC = 449bhp
600cc @ 4bar (694cc) @ 100% @ 0.5BSFC = 528bhp

700cc @ 4bar (810cc) @ 85% @ 0.5BSFC = 524bhp
700cc @ 4bar (810cc) @ 100% @ 0.5BSFC = 617bhp

1000cc @ 4bar (1157cc) @ 85% @ 0.5BSFC = 749bhp
1000cc @ 4bar (1157cc) @ 85% @ 0.5BSFC = 881bhp

 

[Odin]

you have done it again nicko, I think my injectors were
running 95% duty cycle as power station did say that there was
not a lot left to play with :lol: .


rob

 

[Hkondakci]

nikko to list mate, right as always

rgds
habib

 

[Hkondakci]

sorry, meant top list