- Joined
- Mar 19, 2003
- Location
- Denver, CO
I am trying to work through a decent flex fuel tune on my daily driver 240. I have done plenty of E85 tunes on red blocks over the years. But on my daily driver car I wanted to experiment with true flex fuel automatic tuning. I bought the sensor and plumbed it into the return fuel line near the fuel rail and wired it up. I get realistic readings from the %ethanol gauge in Tunerstudio. Everything seems to be working OK. I was getting 12% reading on my standard pump gas 91 octane. I have heard and read the signs at gas stations in Colorado that standard fuel blends contain about 10% ethanol. So that 12% reading seems about right. I added a couple gallons of E85 to my 3/4 full tank of gasoline and the reading climbed to 21% ethanol. Good enough. The sensor reads in a somewhat useful way matching the fuel I added. I think I can tune with that.
I open up Tunerstudio and find the screen for the flex fuel sensor and activate it. And I have to say that I'm somewhat surprised with the basic settings available. I was hoping I could have a totally different set of maps for fuel, ignition, and boost for e85 and gasoline. And some sort of blending between the pairs depending on the ethanol percentage. But below is what I see. I guess it could do the trick buuuuut.
Is a simple linear multiplier for the fuel map and spark map really good enough? It seems overly simplified. My motor is a high compression NA motor with a turbo. The gasoline tune is really tricky and conservative in the timing to make it survive with 12psi boost. It's a funky set of maps especially in the positive pressure parts of the maps. High octane E85 should allow me to set up a more optimum spark map. But all I get is a "distributor twistin" adder of X degrees? Really?
Am I missing something here? Am I the first person to want the flexibility to drive the car around in the wild and fill up anywhere I can?
I open up Tunerstudio and find the screen for the flex fuel sensor and activate it. And I have to say that I'm somewhat surprised with the basic settings available. I was hoping I could have a totally different set of maps for fuel, ignition, and boost for e85 and gasoline. And some sort of blending between the pairs depending on the ethanol percentage. But below is what I see. I guess it could do the trick buuuuut.
Is a simple linear multiplier for the fuel map and spark map really good enough? It seems overly simplified. My motor is a high compression NA motor with a turbo. The gasoline tune is really tricky and conservative in the timing to make it survive with 12psi boost. It's a funky set of maps especially in the positive pressure parts of the maps. High octane E85 should allow me to set up a more optimum spark map. But all I get is a "distributor twistin" adder of X degrees? Really?
Am I missing something here? Am I the first person to want the flexibility to drive the car around in the wild and fill up anywhere I can?