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Originally Posted by bestclimb
Thats pretty cool. Speeking of cool your exaust temps must be pretty low.
What ideas do you have to get timing back to where you are getting peak pressure with the crank 90 past tdc?
When I was thinking about using a carb to get lean for my rig with a vernier type prop knob attached to the distributor and adjust to best power once as lean as I could go.
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Yes the exhaust temps are very low during lean burn
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What ideas do you have to get timing back to where you are getting peak pressure with the crank 90 past tdc?
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This is a issue I'm working on. At anything above 20:1 A/F my timing for max power at light load is in around 40* BTDC. I have a way to control the flame kernel in the prechamber to help this but I ran out of time this last year.
Lean burn is pain in so many ways.
I'm trying to get over a 30:1 A/F ratio to help with NOx but in doing so my BSFC numbers increase drastically. Not good.
If I use my new EGR systems to help NOx I lose power and need more air/fuel to over come it. Not good.
If I drop the A/F ratio down to 22:1 I'm sure I can get 80mpg(before the aero mods) at 55mph with more tweaking with the timing advance,flame kernel adjustment, and pulling more vacuum on the crankcase,but it won't pass emissions on gasoline with these settings and I would have to cheat the system by running two different tuning maps.