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smurfbus smurfbus is offline
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Join Date: Aug 2009
Location: Europe
Posts: 1,481
I'm still puzzled about your AFR gauge readings. If it's showing 10.7 AFR with E85 and the gauge is calibrated for normal pump GAS then when using E85 it should actually be leaner than stoich. That is clearly not the case as you have added 25% fuel over the previous really rich gas tune.

Your gas AFR gauge should read around 8 AFR now! What kind of gauge is it? If it's innovate you can calibrate for E85 with your PC (maybe you did this?) or maybe the AFR you gave was from the dyno and the dyno operator already made the conversions?

Following numbers are from wiki and those max power values are too lean for aircooled engines but there is a guideline for therelationship between gas and E85 and AFR and Lambda.

Fuel AFRst Lambda
Gasoline stoichiometric 14.7 1
Gasoline max power rich 12.5 0.8503
Gasoline max power lean 13.23 0.900

E85 stoichiometric 9.765 1
E85 max power rich 6.975 0.7143
E85 max power lean 8.4687 0.8673

Its cool that you are experimenting with E85 and that would be one reason for me to go EFI if it works out good in the long term. Cooler is better and it's environment safe also.

Last edited by smurfbus; 03-18-2010 at 10:34 PM..
Old 03-18-2010, 09:26 PM
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