The real trick is knowing what kind of AFR's (or lambda) to aim for when running x boost with whatever mixture of gasoline to alcohol that's being used...

B

 

finished the calculator, added in addition to gasoline and meth: E85, E100, Propane, and diesel. Can be found at www.wannaspeed.com/lambda.html

 

I still dont understand why you are doing this?

Unless you are using it to calculate pulsewidths for a base map or something, this information is useless; your wideband, when set to gasoline fuel, will read 14.7 at lambda=1 regardless of what the actual air fuel ratio is. For actual tuning, you just pick whichever conversion factor sounds nice to you and tune to the appropriate values, doesn't matter what fuel you use.

It is good that you are doing this sort of thing, but IMO, if you want to spend the time and contribute, do a bunch of research and make a calculator that outputs theoretical ignition advance values based on charge temperature and pressure, CR, lambda, and rpm. This should be possible if you research flame propogation vs cylinder conditions, although the real way to do it is by instrumenting an engine with cylinder pressure transducers and doing a designed experiment to cover the whole matrix, which is a little side project I have been scheming. There are obviously other variables like porting characteristics that come into effect, but even a series of baseline curves would be a nice contribution to the rotary tuning knowledge base.

Anybody can look up stoich air fuel values, but I have seen very little science on rotary ignition advance.

 

I don't know if you're talking to me or to the OP, but if you're talking to me, I made the calculator for these reasons: To practice java scripting, and to show the relationship of different fuels to lambda. You're right it doesn't matter what fuel you use, you still tune using gasoline figures if no settings are changed in the wideband. The problem is so many people don't graspt that, I've explained it half a dozen times already, I figure the calculator will help people understand. It's also a good reference to get an idea of how much extra fuel you need with different fuels. If you want to build an elaborate calculator that estimates correct ignition values go ahead, but that sounds just as worthless. Considering every engine has different requirements, and to get a rough guidline all u have to do is search. Don't knock my contribution just because u don't want to use it. I've contributed plenty.