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

[garry goodall]

anyone using a fuel computer, apexi neo or simular to reduce the AFR's on their turbo's ?

I know the standard ECU runs very rich on my rev 3, a recent dyno shown low 10s on a run.

the question is what kind of power can be had from trimming the fuel map down to a leaner mixture? is it worth it?

I think i ran 11.5 AFR on my starlet turbo with a piggy back ecu which was deemed safe?

current mods are: Induction kit, Decat, MCB 1.1 bar, uprated intercooler, blueflame exhaust

[djpkins]

no...it's an old way of doing things and not too safe..better to get a mappable ecu,

http://www.lovehorsepower.com/MR2_Docs/Tuning.htm

worth a read.

[Draven]

Get yourself a mappable ECU and get a decent map on it..

[Nic]

Don't bother.

I'd check if the oxygen sensor is working properly if the car is running rich.

[Marf]

Don't bother.

I'd check if the oxygen sensor is working properly if the car is running rich.

The oxygen sensor has nothing to do with on boost fuelling, it only works on at idle, very low load and cruise situations.

[Nic]

The oxygen sensor has nothing to do with on boost fuelling, it only works on at idle, very low load and cruise situations.

Yeah, that'll teach me to not to read the thread properly

[garry goodall]

OK, staying away from them

[garry goodall]

no...it's an old way of doing things and not too safe..better to get a mappable ecu,

http://www.lovehorsepower.com/MR2_Docs/Tuning.htm

worth a read.

not very consistant are they, will look at an mappable ecu

[toyokid]

Another option could be to buy an adjustable fuel pressure regulator?

You need to set it up on a rolling road or run a wideband sensor?

This would give you the option of reducing fuel pressure which has been shown to benefit power and consumption.

Stephen

[Marf]

Another option could be to buy an adjustable fuel pressure regulator?

You need to set it up on a rolling road or run a wideband sensor?

This would give you the option of reducing fuel pressure which has been shown to benefit power and consumption.

Stephen

REALLY bad idea.

[djpkins]

doesn't the oem fpr increase the pressure psi/psi when it detects a rise in the boost pressure....or something trick like that.

[toyokid]

Another option could be to buy an adjustable fuel pressure regulator?

You need to set it up on a rolling road or run a wideband sensor?

This would give you the option of reducing fuel pressure which has been shown to benefit power and consumption.

Stephen

REALLY bad idea.

Why?

[Marf]

Another option could be to buy an adjustable fuel pressure regulator?

You need to set it up on a rolling road or run a wideband sensor?

This would give you the option of reducing fuel pressure which has been shown to benefit power and consumption.

Stephen

REALLY bad idea.

Why?

Because altering the fuel pressure affects the fuelling across the entire fuel map. You reduce the pressure to alter the AFR on boost in the top end and it'll screw the AFR everywhere else.

It's like using a broadsword for removing someones appendix instead of a scalpel.

[toyokid]

REALLY bad idea.

Why?

Because altering the fuel pressure affects the fuelling across the entire fuel map. You reduce the pressure to alter the AFR on boost in the top end and it'll screw the AFR everywhere else.

It's like using a broadsword for removing someones appendix instead of a scalpel.

It has been proven to work with a standard ECU
on a rev 2.

[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.

[djpkins]

popshe...

[nitric4k]

I asked about one of these and was advised against it, for the above reason

so it will be standalone for me to come

[djpkins]

lol...love that bug man...gonna get me every time

[Super_red]

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.

[bobhatton]

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.

How do you think the stock FPR works?