Ok lets assume you have a car tuned to an AFR and the timing at that load/rpm is ideal. Now lets suppose you richen the mixture/lower the AFR. What should you do to the timing, if anything?
Some things, possibly misconceptions, that I've heard in the past:
- Advance timing until it knocks and then back off 1-2 degrees
- A the flame front in a lean mixture burns slower, so more timing advance is appropriate, (intuitively a rich mixture would need less advance)
- More timing advance + more fuel = more power
- Not enough as well as too much timing advance can cause knock
- Too much as well as not enough fuel can cause knock
Please feel free to dispel or confirm any of these statements with good scientific explainations. I've spent hours searching the net for the releationship between AFR and timing and have not found a good explaination.
Thanks!!