ECU retune for Intake Exhaust setup

[BNR32_Coupe]

My friend and I were having a discussion about a simple open air filter intake and exhaust setup. One argument was that the OEM ECU fuel/timing map is configured for the specific layout of the vehicles intake setup, therefore, an improvement in airflow efficiency would do more harm than good in WOT conditions, as the engine would be leaning out.

It just seems so farfetched to say an intake and exhaust setup would require an ECU retune/piggyback controller or else you're just leaning out your car. As far as I know, most ECU's can learn and adapt to changes in conditions, such as improved airflow, but obviously they wouldn't adapt to a more hardcore set up like increased intake piping diameter, cams, etc. Can anyone verify this or add some input?

[ncrx]

There's always room for improvement, the oem ecu is very conservative and already on the rich side and easy on the ignition. If the ecu detected knock it would pull back timing anyways and put you into the knock maps and it'd run like ass.

There are gains to be had even in stock trim on a retune.

It really depends in what part of the fuel map you are putting yourself into, whether nissan set it up to dump fuel in this region or to lean out. But my guess is its very rich to protect the engine and for longevity.

For example, on my gti-r if you turn up the boost to 1bar from factory .7bar, you can still run it safely but it runs uber rich. The extra load sensed by the maf pushes it into a super rich safety margin region of the fuel map. You can run it in this state at the expense of running very rich, possibly fouling plugs, sensors, and washing out your cylinder walls and oil.

If you look really closely on the top right corner of the fuel map, you'll see what the standard map is set for. a/f's in the 10's
http://www.plmsdevelopments.com/imag...ne_screen3.jpg


I'd consider a nistune to do a map trace and retune. it'll tell u exactly whats happening and allow for quick minor adjustments to your mods and for only a slight cost over an safc for example.

[Leopold Stotch]

IMO

Stock tune is rich so adding an intake and exhaust so tuning it doesn't deem neccesity.

plus many new ECUs can learn and adapt.

also if it were bad for the engine the knock sensor would come on.

[ncrx]

tuning isn't a necessity for a minor bolt on i agree, but there are gains to bad in fuel efficiency, power, and driveability if you were to clean up the tune.

also to the original poster, you can't assume what the ecu is doing unless u look at the fuel maps, a/f ratio, and do a map trace.

[defearian]

Originally Posted by ncrx

It really depends in what part of the fuel map you are putting yourself into, whether nissan set it up to dump fuel in this region or to lean out. But my guess is its very rich to protect the engine and for longevity.

So are you saying that running a little rich is good for your engine?

[bcrdukes]

Not necessiarly good per se but it's a little rich from the factory to prevent you from blowing your motor as a safe measure. Also, if a knock sensor detects knock, it will retard the timing to save you from blowing your motor.