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Injector and fuel pump sizing
Nitrogeno25 - 16/2/12 at 04:07 PM

For my Duratec installation:

I got 250cc/min injectors and aiming for 160-170bhp.

Am I OK in thinking that at 100% duty cycle (it shoudn't be), 4 injectors equals to 1 liter/min. So a fuel pump capable of 60l/hour in theory should be enough.

I'm after a 105 l/h fuel pump (Bosch in-tank). That 60% is a good safety factor? Maybe for reaching 200bhp with some later upgrades?

Many thank!


matt_gsxr - 16/2/12 at 09:46 PM

Those numbers add up correctly to me.
Sounds like a good plan.

Just as an aside.
If you increase the fuel pressure above the standard 3atm, then you can get more flow out of the injectors (if you need it), but this reduces the fuel pump flow-rate (at least for the walbro ones).

Matt


Nitrogeno25 - 17/2/12 at 11:22 AM

quote:
Originally posted by matt_gsxr
Those numbers add up correctly to me.
Sounds like a good plan.

Just as an aside.
If you increase the fuel pressure above the standard 3atm, then you can get more flow out of the injectors (if you need it), but this reduces the fuel pump flow-rate (at least for the walbro ones).

Matt


Thank you very much!

So it seems OEMs use way oversized pumps. This model is used in VW 1.0 and 1.6L engines (70hp and 90hp)!


coyoteboy - 17/2/12 at 11:54 AM

Probably just bulk-buy a mid-range pump and use it for all - saves hugely on manufacturing costs.


Nitrogeno25 - 1/3/12 at 04:26 PM

I've just receive a response from Webcon about their in tank fuel pump rated at 75l/h and they told me they recommend the pump up to 250bhp

It seems every car manufacturer use way oversized fuel pumps, we will see....


coyoteboy - 1/3/12 at 05:08 PM

Fairly well spec'd for 200+ KW, with some FOS, at 75 l/h.