Alky and widebad readings

[QwuickTurbo6]

Razor, I couldn't help but notice that your sticky suggests a target wideband A/F ratio of 11.9-12.0. It seems like that is really lean from what everyone is saying in this thread???

 

[Razor]

Razor, I couldn't help but notice that your sticky suggests a target wideband A/F ratio of 11.9-12.0. It seems like that is really lean from what everyone is saying in this thread???

Thats an old sticky :redface:

Needs a little updating.. thanks for bringing it up.

 

[Slow91z]

Thanks for all the info guys...This turned out to be a pretty good thread, with good info.

 

[pacecarta]

heres something else to consider
if you run X.xxx on c16 at 80% duty cycle..
then run the same time on 93 and alky at 72 % duty ...yes you displaced 10% of the fuel but you didnt replace it with 10% alky

your mix is not 90 fuel/10 alky

to get the same times on 93+alky you need to get back to the original btu content of running 80% injector duty of fuel only.
that takes more than just replacing the 10% liquid you dropped with the injector duty because alky doesnt net the same btu per lb as gas fuel , you need 2x the alky for that so you will actuall be adding 20% meth to reach the same btu as c16 but with the added benifit of cooler air and cylinder temps so the alky mix can actually outperform c16 ...and has

 

[bison]

heres something else to consider
if you run X.xxx on c16 at 80% duty cycle..
then run the same time on 93 and alky at 72 % duty ...yes you displaced 10% of the fuel but you didnt replace it with 10% alky

your mix is not 90 fuel/10 alky

to get the same times on 93+alky you need to get back to the original btu content of running 80% injector duty of fuel only.
that takes more than just replacing the 10% liquid you dropped with the injector duty because alky doesnt net the same btu per lb as gas fuel , you need 2x the alky for that so you will actuall be adding 20% meth to reach the same btu as c16 but with the added benifit of cooler air and cylinder temps so the alky mix can actually outperform c16 ...and has

Keep in mind that all pump gas varies in ethanol content too. Not good if consistency is expected. You dont have to get back to the same BTU rating either. If methanol is 6000btu/lb and gasoline is 12000btu/lb (both of those numbers are hypothetical)you wouldnt need 2x the alky to make the same power. It would be less than 2x even though the heat energy is half as much per lb. The alky pulls out so much heat it doesnt need to be run 2x as much volume based on its heat value per lb. Alky is also much more consistent than gasoline and will make very similar power based on a wider range of a/f's than gasoline. Gasoline is way more sensitive to a/f ratios.