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Old 29-07-2006, 08:20 AM
simple simple is offline
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Join Date: Mar 2006
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Quote:
Originally Posted by JohnA
Quote:
Originally Posted by simple
...First, talking about tuning new car for WI. It has been mentioned that you want AFR about 12.5 as cars under boost run normally richer. Well here is a third gear pull of my car. It?s totally stock:
We are not talking stock cars here mate, the manufacturer has optimised all parameters during stock operation.
If you inject water on a stock car you are unlikely to make any more power. Most likely you will *lose* some.

Understood. This means that levels leaner that 12.5 will be neded. I refer to this part to indicate that 12.5 can be not "lean enogh" for some WI applications.

Quote:
After 4500RPM there is boost reduction due to turbocharger going outside efficiency range....
How do you know that? Are you datalogging the solenoid's duty rate?

I datalog solenoid as well. It is ECU who pulls boost down by changing duty cycle. AUDI uses small KO3 for 1.8 engine. That how I manage to get 7PSI @ 2000RPM. According to AUDI tuners, KO3 going outside it's effcency at 5000RPM so boost is reduced to keep it with in the map's parameters. I can do a plot for you on the KO3 map if you are interested

Quote:
Look like new cars run lean stock. My cruising AFR is 14.7@ light load(80Km/h)
That's how it's meant to be.
It is high throttle/high load conditions that AFRs are meant to go richer.

Understood. I mentioned it here as piople where stating 14.5 as lean "low load" operation

Quote:
Second, according to stock ECU knock sensor reaction KNOCK been detected throughout whole RPM range. Under knock I mean not audible knocking but early knock detection by ECU(mild knock).
Are you talking about the knock sensor output, or the ECU's interpretation of Knock? These are two different things, the sensor produces output all the time, the ECU has filtering algorythms to make sense of it all.

Trying to extract algorythms is what we are working on now. This graph contains V (voltage) of each knock sensor for each cylinder. I was refereng to KNOCK as fackt not the bakground noise.



Quote:
...It is also noted that poor fuel quality will make it more intence as well
this is very true.
However, I doubt that you are getting any knock on a stock car running stock boost and the recommended fuel. Even if you do it will be on a very hot day and at max torque revs if you boot it real hard. The ECU will adjust timing a bit and that's that.
AUDI has ECU which is slow to adapt. As I always use high RON fuel it adopted to it. Accaisinally I put "normal" fuel recomended by AUDi for datalog purpuse and i notice that a lot more knock is present on datalog. It takes about one full tank of fuel for ECU to re-adapt to new petrol and ajust it's map to suite.
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