Discussion and questions related to the course Ethanol & Flex Fuel Tuning
After the process of lets say we find MBT @2500rpm in 100kpa of 25° & @6000 rpm in 120kpa of 30°. How do I calculate what to do in every other rpm/kpa? Is interpolation within the cells of the powerband? (Like the sections of the target Lambda Chart, by section High boost, medium boost, cruise ect.
If you can set your boost control to at 120 kPa target, then you can make ramp runs to the RPM limit and monitor knock and try different ignition timing to find the maximum power. Either follow the trend or repeat with a higher boost target. The Dyno will tell you what ignition timing produces the best torque, and your knock monitoring will tell you if you are knock limited.
Thank you for your response. What I mean is, how do I go about completing or filling in the rest of the timing table. If I set MBT at 2500rpm 30°, do I set the entire "Cruise" section like in the chart attached to 30°? Or am I going to interpolate then guess while doing a ramp run. My question would probably make more sense if I ask, how do i get my ignition map close without a dyno. Am I going to just advance the entire map until i find knock. My car isn't knock limited (honda k20 boosted on E85)
Sorry, building an accurate ignition map for a boosted engine from scratch requires a dyno, preferably a load-bearing dyno.