APEXi SAFCII on gZe???

[NoHachi]

Hiya,

I'm not sure of what the VFC will actually allow you to do, but if it allows some form of fuelmap alteration then it will be fine..

The point i was trying to make was about recognizing and keeping track of your actual fueling needs. Its kinda covered by the rest of the posts in the thread...maybe an example:

First of all: a ordinary lamda is not a mixture meter, but a mixture gauge..The difference is that a mixture meter shows you the value of the mixture, while a gauge is more of a on-of switch. It switches at lamda =~1 and is pretty unreliable everywhere else..

Now the way I would tune a car, would be to hook up the WBO2 and start driving the car around while logging. You try and cycle through all load conditions and all rpm bands, continually logging the corresponding mixture. This could take up quite some time as there are many many different combinations that the car does not see very often..Its basically the way a car is tuned on a steady state dyno at the factory..
When you collect all the data after two weeks or so..the lambda number not only tells you how the mixture was, but also how much% fuel you have to add to get it to lambda=X..There are plenty of programs out there that calculate the efficiency of the engine from that data (VE-curve) and then accept a "desired" fuel curve as input and report back with the % changes that you have to make at each RPM/load intercept point..

Compare that to the usual "dyno"tuning procedure..A couple of runs through the gears (usually only at full load..thats just ONE of the 12 load settings that the ecu uses) and the corresponding 02 output.. Its a quick and dirty way of doing things, and could be fine, but nowhere near the accuracy that you could have with the other method..

Also a wideband cannot only tell you whether a mixture is lean, but whether it is dangerously lean..a nice precaution in any boosted car.. It also allows you to diagnose and spot any irregularities in the fueling of the car before they become a problem..kinda like the fuel pressure gauge.

Now if you take that data, and tinker around with the AFC, I'm confindent that you would learn alot about the engine and tuning and produce a very good map in the process.
The other method might work as well, it would probably be an improvement over what you have now. Its just that dyno time is very expensive..so a 200$ WB02 becomes a very attractive option.

PS: datalogging=on any Laptop etc
WBO2 has a narrowband simulation output that you can feed your ECU with..So ECU gets ordinary lambda signal, indicator on dash gets WB signal.