Race Engine Forum UK

Hello guys.

i'm working on a Lancia 16V turbo engine with the magnetti marelli IAW 4WG/P8 ECU.

Does anyone know if this ECU is able to adjust fuel injection times accordingly when the fuel pressure is increased from a 2,5 bar model to a 3 bar model.

In other words, will it recognise there is actually more fuel injected and offset the fuel map?

Reason i'm asking is that i have to drive a couple of hours with this setup before arriving at the person who will remap the ecu and i'm scared of overfueling, dilluted oil and bore wash.

Thanks for the help.

Personally I would swap pumps when I get there.

When you double the fuel pressure you dont double the fuel, the increase would be less than 5% increase between 2.5 and 3 bar.The ecu under lambda control (less than 4k rpm) would be able to adjust for this, it may be alittle rich but within tolerances of the engine at worst.

Don't drive it hard..

EDIT

You should have a regulator at the engine end so would still run 2.5bar until this is adjusted.

evo1 wrote:
In other words, will it recognise there is actually more fuel injected and offset the fuel map?


Thanks for the help.

In short, no. Not on its own, it needs remapping for that.

Without having details of what you have done and why you are expecting 'overfueling, dilluted oil and bore wash' I'm sorry, it is impossible to provide any further help.

Xavier, hi

There is a simple answer to this. Unless you want to risk scrapping the engine, do what I would do and get a trailer and take it to the dyno on a trailer.
This does not answer your question, of course, but that is nether here nor there!

Never drive a car when the fuelling (or ignition) calibration is suspect, period!


GC

No, but if it has an O2 sensor it will adapt to some extent on cruise and idle.

Thanks for the answers.

Yes, it has an o2 sensor, that's why i was wondering to what extend this ECU is capable of altering the mixture.

I'll probably do what GC says and put it on a trailer.

evo1 wrote:Thanks for the answers.

Yes, it has an o2 sensor, that's why I was wondering to what extend this ECU is capable of altering the mixture.

I'll probably do what GC says and put it on a trailer.

If you can it is of course best.

Just for sake of completness, closed loop fueling correction is limited to -20 to +20% on that particular type of control unit.

If it fails to achieve it in cruising conditions over some adaptation time, it will throw out an error code.

Best regards,
Nikola