E30 or e50 blending general rule of thumbs

[wifeys-ST]

Everyone running ethanol blends knows how to calculate and blend e10 pump with e85 to get e30 or e50. There are plenty of calculators that help.

Purpose of thread here is to share any general rule of thumbs for mixing without needing to calculate.

As I start running e30, I’ll post what I find. Figured I would start the post now and see what the community wants to share.

 

[2020FordRaptor]

Testing at the pump is a must, cheap test kits out there. It will never be pure E85, usually closer to like e72 from what I’ve seen. Ethanol sensors also help. When calculating, remember that you still have pump gas in the tank, and to take it into account. I usually let it sit and mix for a couple minutes after filling up, maybe just superstition but that’s what I do.

 

[UNBROKEN]

I’ve been mixing for over 5 years now. I haven’t tested fuel in close to 5 years.
I have the E85 part on my app set to 80 and guesstimate the fuel level. I have a sensor so I can watch the blend and I’m very rarely more than 5 points off and if I am it’s always on the low side.
An E50 tune is good from 40 to 60 so you have a huge range to still be considered “right”.
I just don’t worry about it that much…after a month or so you’ll get comfortable and probably won’t either but on no planet am I testing E85 every fill up when that’s usually 3X a week at least.

 

[BuckStrickland]

Testing at the pump is a must, cheap test kits out there.

That's not entirely true unless you're running completely blind. Anyone with an ethanol setup should be getting a fuel it or p3 to read the current mixture. With time, it will be almost second nature.
I.E. " I have almost 1/4 tank, so I have about 5 gallons left. It's summer, so this gas station is normally around 70%, so If I pump X amount, i'll have around X% when I'm done."

I usually test once in the late spring , once in the late fall, and the stations usually stay around the same % until the weather changes for the season.

If you pump the ethanol first, then the gas, it mixes up more quickly and will usually read almost instantly without changing much as you drive.