e85 percent

[xc_SS/RS]

Highest content I’ve seen at the pump I believe is 81 but it’s normally between 70-80%

As long as the scales are set up well on the tune you can safely run anything from 0-100% ethanol. It’ll scale the timing and add fuel depending on alcohol content seen at the sensor. So it being tuned on 71% is meaningless if the scales are set up well

[eLeSthree]

Originally Posted by fleebag

Since switching to E my avg is around 74ish% as well. And I'm in the Jacksonville area. Granted I just started tuning it and the most I have seen is 78 or so.

My spark/ fuel comp is set at 20%E x .85, 50%E x .90, 80%E x1.0
So if I'm hovering around 74%E its "only" adding .90 of the extra timing? correct?

Like OP, I too was 850ish but on 93 only. I added meth and played with the tune. And now I added the E and not certain of gains. However, the Butt dyno confirms more than 10HP LOL.

I meant between 71% and 85%. Not between 93 and Ethanol.

[Badbubba]

Originally Posted by xc_SS/RS

Highest content I’ve seen at the pump I believe is 81 but it’s normally between 70-80%

As long as the scales are set up well on the tune you can safely run anything from 0-100% ethanol. It’ll scale the timing and add fuel depending on alcohol content seen at the sensor. So it being tuned on 71% is meaningless if the scales are set up well

71% was used to setup the scaling/equation for their setup. So it would not be meaningless. A larger span of ethanol content between the base 93 and "E85" should yield more accurate results. I asked the OP what the ethanol content they had, combined in the tank, for the flex fuel tune. There could have been a 1/4 tank of 93 and then "E85" added. And as we know, E85 can be between 51% to 85% ethanol. So if the ethanol content was low, there may be room for improvement. But probably not worth the fee for another tune. I would not just extrapolate values at a low ethanol % and take for granted that the scaling generated will be linear and accurate at E100.

[eLeSthree]

Originally Posted by fleebag

Since switching to E my avg is around 74ish% as well. And I'm in the Jacksonville area. Granted I just started tuning it and the most I have seen is 78 or so.

My spark/ fuel comp is set at 20%E x .85, 50%E x .90, 80%E x1.0
So if I'm hovering around 74%E its "only" adding .90 of the extra timing? correct?

Like OP, I too was 850ish but on 93 only. I added meth and played with the tune. And now I added the E and not certain of gains. However, the Butt dyno confirms more than 10HP LOL.

So you are adding 85% of your additional FF timing with just 20% ethanol content? That seems pretty high. Mine is 10% .125 20% .250 50% .625 80% 1.00.

But then again, I dont know whats in your FF,Gas,Alc tables. My car has never seen 93 since I added FF, lol. Timing is about 21 all in.

[xc_SS/RS]

Originally Posted by Badbubba

71% was used to setup the scaling/equation for their setup. So it would not be meaningless. A larger span of ethanol content between the base 93 and "E85" should yield more accurate results. I asked the OP what the ethanol content they had, combined in the tank, for the flex fuel tune. There could have been a 1/4 tank of 93 and then "E85" added. And as we know, E85 can be between 51% to 85% ethanol. So if the ethanol content was low, there may be room for improvement. But probably not worth the fee for another tune. I would not just extrapolate values at a low ethanol % and take for granted that the scaling generated will be linear and accurate at E100.

I think you misunderstood me. Once the scales are set up well, it being tuned on 71% means nothing since it’ll run just as well with 85% vs 25%.

All I put in my car now is enough to get it to 30-40% e content and even if I touch up my fueling for this percentage it’ll still run perfectly with 85% See what I mean?

All I’m saying is once the tune is done, you can run any alcohol content.

[Badbubba]

Originally Posted by xc_SS/RS

I think you misunderstood me. Once the scales are set up well, it being tuned on 71% means nothing since it’ll run just as well with 85% vs 25%.

All I put in my car now is enough to get it to 30-40% e content and even if I touch up my fueling for this percentage it’ll still run perfectly with 85% See what I mean?

All I’m saying is once the tune is done, you can run any alcohol content.

Yes. I just wanted to confirm there was "enough" ethonal content to tune and scale correctly for their vehicle. It wasn't that I was stating being tuned specifically on 71%. 👍