[Mk2] [Turbo] Fuel computers - worth it?

[Marf]

Adjusting base fuel pressure WILL affect the fuelling across the board, on boost, off boost, low revs, high revs, EVERYWHERE.

Reduce it and you lean out across the fuel map, increase it and you'll richen the entire fuel map.

It's using a sledgehammer to crack a nut, a total and utter bodge.

But hey, it's "proven", so believe what you want.

Adjusting the base fuel pressure will yes but what about a rising rate FPR? this will only start to increase fueling when boost is applied so off bost and low boost will remain the same. You can use a wideband to set up the additional fuel pressure and as long as the base pressure is the same it wont effect the cars off boost running. Reducing AFR by increasing fueling.

wont help with ignition retard though.

The OP is talking about taking fuel out, not adding it.

[Al-sw20]

Reducing AFR by increasing fueling.

wat

[toyokid]

Fueling computers used to be popular as a cheap alternative to fully mappable
ECUs, but now that ECUs have come down in price there seems little point unless they are very cheap and you treat them as a quick fix.

I have Apexi power fcs' on both my rev 2 and rev 3
but prior to this I tightened the spring on my rev 2 AFM which improved the power and economy. It altered the fueling across the rev range, however on closed loop the O2 sensor controls fueling not the AFM.

On much the same basis
I don't see how lowering the fuel pressure in a controlled environment e.g. rolling road would be bad and indeed have potential gains
in open loop when the car is trying to run standard "high" afrs'.

Each to his own.

Stephen

[Peter Gidden]

Adjusting base fuel pressure WILL affect the fuelling across the board, on boost, off boost, low revs, high revs, EVERYWHERE.

Reduce it and you lean out across the fuel map, increase it and you'll richen the entire fuel map.

It's using a sledgehammer to crack a nut, a total and utter bodge.

But hey, it's "proven", so believe what you want.

+1

Reducing pressure can also affect spray pattern and atomisation. Most injectors are much happier running a higher pressure than stock, as opposed to lower.