I have an FS station near me that has a variety of e-designatted fuels. Unforutnately, e30 isn't one of them. Yes, I know I can mix e levels to approximate e30 but that's a hassle. They do, however, have e50. Does anyone have any experience with e50 and the JB4? Which map did/do you use? Any other issues?
The E30 recommendation is to keep from hitting fuel flow limits (from E85's lower stoich, multiplied by the general increase in fuel needed to match more boost/air). Seems like that number was set conservatively, with references about running up to E40, so by E50 you're likely hitting that limit at upper revs / high boost.
Day to day you're definitely going to take more of a hit on mileage. With ethanol having ~30% less energy per unit, an E30 mix will cost you about 9-10% mileage, while an E50 mix is going to be 15%. The E30 mix doesn't have to be precise, so adding 3.5-4 gallons per full tank (2 gallons for half tank, 1 if you're at 3/4 tank) followed by premium will get you close enough.
I have an FS station near me that has a variety of e-designatted fuels. Unforutnately, e30 isn't one of them. Yes, I know I can mix e levels to approximate e30 but that's a hassle. They do, however, have e50. Does anyone have any experience with e50 and the JB4? Which map did/do you use? Any other issues?
Six gallons E85, rest pump, is a good starting point for the factory flash. With our BEF loaded a stronger mix can be used to a point, and with CPI more or less as much as you want.
I would have issues if I went over E45 with a JB4 and cpi. E30 is about max without cpi or ecu tunes.
Something else to note, you don't know what they are mixing to get that E50. The station might be mixing 89 and E85 to get to E50. The overall octane will be lower when compared to mixing 93 and E85.
So I live in the south (from cali) which makes things pretty spread out. Towards an empty tank I will usually add 12 gallons 93 octane at Shell, then drive a little over 11 miles and drive to Casey's where they have E85. I put in around 4 gallons of E85 and run Map3-4. Logs have looked good, I'm a spirited driver but not a racer, never had an issue running this mix. Just running to multiple gas stations kinda sucks to get it all together.
PS: My work is located next to Shell and my home is located next to Casey's so it's not an out of the way drive for me.
E85. The tank is 15.9 gallons but "empty"/gas light is more like 14, 14.5. 10 gallons of 93 and 4 gallons of E85 will get you just over E30 and just over 96 octane, if I recall correctly, so call it a gallon of E85 per quarter tank. A little more if you're stuck with 91 or have "E85" that tests more like E60.
