Yep. I can only run e85 late April to early October in my area for this reason. The good news is it gets up to 90% and stays there most of summer.

 

My Demon 170 has almost 500 miles on the odometer. The car arrived with a full tank of E-10. The dashboard display accurately confirmed the presence of E-10. How do I know? I was the one squeezing the nozzle on that initial fill. Since then I have run several tanks full of E-85 from QwikTrip. The inclusion of their E-85 finally topped out as E-59 on my display. This mystery was quickly solved when I went onto their website. Here is what I found:

E-85 fuel contains 51%-85% ethanol and the rest gasoline....

https://www.kwiktrip.com/our-story/fuel

With E-59 the horsepower is capped at 1010.

Mine is E79 to E81 here in California. But with VP E85 out of the Pail it reads the exact same. So the sensor must be off a little.

 

My Demon 170 has almost 500 miles on the odometer. The car arrived with a full tank of E-10. The dashboard display accurately confirmed the presence of E-10. How do I know? I was the one squeezing the nozzle on that initial fill. Since then I have run several tanks full of E-85 from QwikTrip. The inclusion of their E-85 finally topped out as E-59 on my display. This mystery was quickly solved when I went onto their website. Here is what I found:

E-85 fuel contains 51%-85% ethanol and the rest gasoline....

https://www.kwiktrip.com/our-story/fuel

With E-59 the horsepower is capped at 1010.

This is why I don't use E85. I can't get consistent concentrations here and ordering barrels of the stuff from VP is stupid expensive. The consistency of E85 at most gas stations varies wildly... sometimes even at the same station over the course of a week. It all depends on how it's stored and if it gets water in the tanks or not and what their supplier mixes at. Which, varies, all the time. Every time you fill up, you should test the fuel first. It's not as critical on a flex tuned car, but if you ever get a car that has an aggressive tune that needs a specific concentration, you can really do some damage by putting in weak E85.

This is also another reason why I didn't opt for a D170. I knew I couldn't get high concentration E85 around here pretty much anywhere. I'd realistically never get to see it in 1,000hp mode unless I mail ordered fuel.

 

If I remember what my builder said, my e85 tune is good for anything e60-ish and up. Every time I have sampled the pump e85 I get from Meijer its well above that, mostly in the 80s sometimes close to 90. I think i sampled another station Sheets or Kroger and it was right at 60 at the time? So I have been sticking to meijer in the summer and back to the 93 tune with some renegade 112 race gas mix in the winter.

 

170 gets to 1025 with 65%. Buy a can of 98% and mix to get above 65%. I dont worry about 85% unless racing.

 

Summer months you should see that content go up. Ive seen as high as 90% and as low as 60%. I have one station that is 85% on the dot all summer luckily. Anything below 80% and the car gets grumpy.