It Takes Good Timing

[hombre]

Burn rates are different for a supercharged engine, so ignition timing must be significantly different. Here's what I've learned from TFX:

Air Fuel (AF) Mixture Burn Rates

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The burn rate or energy release rate of the combustion process for cylinder 1 (combustion cycle 353) is displayed above. The blue line indicates how quickly the AF mixture is burning relative to crank position and the pink line indicates the percentage of the AF mixture that has been combusted relative to crank position. For this combustion cycle only 3% of the AF mixture is combusted at TDC, 20 % at 10 ATDC, 60 % at 20 ATDC, 83 % at 30 ATDC and 100% near 60 ATDC. Since the engine is supercharged the combustion process occurs much more quickly than for a naturally aspirated engine with the same ignition point. Although the combustion process is fast it occurs too far ATDC to generate maximum power. Adjusting the ignition timing to a more appropriate value would result in significant increases in power for the same amount of boost. When timing adjustments are made the data logger data will indicate when the timing is correct and if any detonation is occurring.

 

[mjbell1]

Tdc

I guess the answer to the question was there a knock
sensor was a negative. It certainly would have helped
resolve your timing/tuning problems.

 

[hombre]

There's no knock sensor on the R3. TFX uses pressure transducers to collect cylinder pressure data for their software. The most accurate ones require drilling the cylinder head, but they also offer spark plug transducers (ah so... verrry clever these Japanese).