Hi Matt, when you write 600 or 700 rpm - do you mean engine rpm or prop rpm??
My engine idles at 1700 rpm (engine), because that's where I set it: divided by 2.85 = 596 prop rpm - my engine and the gearbox get rough around 1550 ... so I keep it away from there.
Don't know absolute AFR numbers but my engine usually idles richer than 14.7 (stoich) when cold but after it warms up I find it idles better (post-flight taxi back to hangar) a bit on the lean side.
Timing - set as per Tracy's manual (25 deg? BTDC) and have never moved it, as EC2 advances timing with rpm ...
Jeff
What AFR and timing are people running for idle, taxi, takeoff, climb, cruise, descent?
idle = 11afr, 20 timing
I seem to have to be around 11afr for it to stay alive. Still trying to get it to idle around 600rpm, maybe bump it up to 700rpm to be smoother without dieing and shaking apart.
taxi / takeoff / climb = 13.2afr, 28 timing
cruise - not sure aft, 28 timing
decent - not sure aft, 32 timing
Not sure what the plane likes. I tried 14afr, but the MAP really get's low and engine shakes. Guessing it should be more rich?
I attached the timing table and split rotary table (second email). Not sure how to tune timing, I just want safe values for now.
- Matt Boiteau
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