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High fuel demand?
carl M - 6/10/17 at 08:35 AM

Hi,

Vehicle is 2l Zetec with GSXR t/b's, 240cc/min, deadhead fuel system, with MS3 running it. I recently changed from running a sump fuel tank to a swirl pot due to some fuel starvation. (see noisy fuel pump thread below)

However my fuel requirement is particularly high (and increased after adding swirl pot).

At idle the VE is 31, at 5k rpm I'm around 180!!

The fuel pump(s) are over specced (250bhp) but I'm still not sure why the required fuel is so high. The only think I can think is that the dead head fuel system is something to do with it.

Any idea's?


peter030371 - 6/10/17 at 10:11 AM

What pressure regulator are you running and what is it set to?


carl M - 6/10/17 at 10:31 AM

One with a gauge set to 3.5bar


cliftyhanger - 6/10/17 at 11:19 AM

injector size and Pressure set correctly in the ecu? they are the obvious things that get left, and then the VE table looks wrong.


carl M - 15/10/17 at 03:07 PM

Sorry for the delay in replying, just got back from travelling, injector size is correct, required fuel is 14.6

Ever since I've added a swirl pot the I've needed more fuel. (HP pump has stayed the same)


coyoteboy - 15/10/17 at 08:28 PM

5000rpm full load? 180 seems ok. 5Krpm no load, seems a bit wrong.


carl M - 16/10/17 at 06:50 PM

At tickover, 0% throttle the VE table is 35

At 5k 100% throttle the WB wants about 180.

Is this about correct?


coyoteboy - 16/10/17 at 09:50 PM

Ideally you'd scale your req fuel to give you a VE table which uses the full 0-255 range, without taking your injectors over 80% duty cycle.

That gives you the best possible resolution of fueling availble. If you scale req_fuel (for daft example) so you use 0-10 on the VE table, you'd have 10 fueling levels (and so be fueling badly anywhere not exactly requiring one of them). If you scaled it so you used >255 you couldn't give enough fuel.

[Edited on 16/10/17 by coyoteboy]