Ethanol tuning methods

Hi, I have seen some tuners just increasing VE% for ethanol tuning. But this cannot be the correct way. What is my thought is just use a static injector trim.

How do you do it?

The answer depends on the ECU. Sounds like you are talking about ECU without fuel mass modeling, so the fuel table is not really VE%, but just injector pulse width % of some base value. You mention tuning for ethanol, but if you really mean flex-fuel tuning, then I would think it could be done with some kind of compensation table that used the ethanol percentage, to as you pointed out make a single injector trim.

Thank you for your reply.

Is there any general rule of thumb for % increase when going from gasoline to ethanol? I hear its around 40%.

I might have to do some fuel mass calculation.

I would use your wideband Lambda to find out. With the proper compensation, you should get the same Lambda reading regardless of fuel. You will need to add whatever amount of compensation. Start with 35-40% additional pulse width and tune from there.

One of the fastest ways to get to the ballpark is to reduce injectors scaling accordingly...

Thank you guys, just as I thought!