ITBs again! 1108cc standard ECU

[tpv]

This has been discussed a lot, people mention that most are too large, so the low gas speed effects atomisation, BUT:

IF the injectors are just before the port, IE standard position then the gas speed is identical, as effectively it's the same as standard, the gain coming from removing the restrictions at the standard throttle body, shorter tuned length etc.
In fact the gas speed will be greater than before at full throttle .

I've even seen people use standard ECU and injectors as modern injection systems self correct/ self learn using lambda sensor to keep afr correct - although on modern cars this is fairly lean, so can be improved.

I saw one car, that was fitted with 38mm Kawasaki 600 ITBs, even passed MOT with no tuning.

The question is, wouldn't a big single body be just as beneficial, just a long intake length?

 

[bugsymike]

Just a thought but would a good ECU be able to regulate individual injectors for balance in the same way diesel ones do?

 

[tpv]

The ECU can only adjust mixture based on all 4 cylinders output, one sensor in main exhaust.
Can diesel ECU regulate individual injectors?
On a diesel the peitzo electric sensor can detect knock an vary timing of injectors because on a diesel injectors control ignition also but as far as total quantity injected even diesels have lambda sensors in exhaust after the 4 into 1 section so oxygen is measured using sensors that can't tell what individual cylinders afr is as far as I'm aware?

 

[bugsymike]

The ECU can only adjust mixture based on all 4 cylinders output, one sensor in main exhaust.
Can diesel ECU regulate individual injectors?
On a diesel the peitzo electric sensor can detect knock an vary timing of injectors because on a diesel injectors control ignition also but as far as total quantity injected even diesels have lambda sensors in exhaust after the 4 into 1 section so oxygen is measured using sensors that can't tell what individual cylinders afr is as far as I'm aware?

I have had readings on my 2010 Scudo, but nothing to hand at present so this is off a VW Diesel.
Also on my Scudo the balance corrects to 100% as revs brought up, there is a lot of extra functions on later diesel ECUs including when doing a onboard DPF clean Regen etc. the length of injection time as well. All well beyond me, I just thought a petrol ECU on a multi injection system would have similar capabilities.

 

[tpv]

On diesels they have multiple injection cycles, pilot burst, then different quantities as the pressure rises.....BMW even have 2 injectors per cylinder.
A petrol injects into the intake air stream, in this case, mixture is controlled by opening time with a single shot every 720 degrees, intake temp and pressure (map/ combined map temp) , rpm and throttle position tell the ECU how long a pulse to send to each injector.
Fuel rail is of a known pressure so opening times have a definite fuel quantity...... That and witchcraft...

 

[bugsymike]

That and witchcraft...

It is to me, when I started in the Motor Trade in 1969 a twin choke Weber was about the most complicated fueling system, then a bit later on Mazda RX3s and 4s with four choke carbs on the Rotary engines, then early Bosch injection on Mercedes 350 V8s, followed by pre common rail and ECU diesels.