Ahmet,
you make some iteresting points about the AFM, and since i have a spare i was about to go home and try it. BUT.... as i thought about it more, modifying the AFM doesn't make any sense. Here's what i think. if the AFM is fully open at 1700-2200 rpm at full throttle, drilling holes in the door won't let any more air flow through, because nothing would need to flow through the door, because all the air is flowing around the door. Right? Therefore modifing the door, and spring tension would only reduce restriction and increase power at part throttle, or under 2200 rpm. But, at part throttle, if you need more power, just push the gas pedal farther. Under 2200 rpm, most of us won't load the engine at that rpm. there isn't much power there anyway, besides loading an engine at low rpm is not good for the bearings.
I think it would help throttle response though.
2. Altering the temp signal. I will have to preface this part by saying i do not specifically know how the Bosch Motronic DME is programmed to respond, but i will assume it responds the same as the majority of other engine control computers. Most computers take the signal from the O2 sensor as gospel, they will ignore all other sensors to please the O2 sensor. Therefore if you F_ with the temp sensor signal, and tell the engine to feed more fuel, the O2 sensor will tell the DME that it's running rich, and the DME should back off the fuel. Regardless of how cold the DME thinks the engine is, if the O2 sensor says the engine doesn't need more fuel, it won't give it any more. This is also why i think screwing with the 6-position fuel/spark adjustment switch on the DME won't do anything. And on most engine computers, the O2 sensor takes over fuel mapping as soon as the computer starts seeing valid readings.
Now maybe you could F_ with the O2 sensor signal. but this might not work either because of the non-linearity of the O2 sensor. I'm not sure exactly how far on either side of stoichiometric the sensor readings go to hell, but it's not far. I know some of the new cars have wide range sensors, but i know absolutely nothing about them.
I'm not trying to shoot your ideas down, i think they certainly need exploring, but i just wanted to bring up a few points you may not have thought of.
Mike
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