Straight e85 on an ex-t

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Acraig3

Acraig3

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Nice job, OP! I thought the flex kit allows you to run up to 37% blend and still maintain max power? Are you still on straight E85?

I going to keep it simple and only mix 2 gallons of E85 and regular (87) gas on my EX-T (Flashpro Stage 1) and be happy with the result (I've very low expectation as I'm already happy on Flashpro); it's mainly a family car and I only get to drive it on the weekends. Happy tuning :)
I am indeed still running a straight mix of e85. My tuner is very good at his job, and suggested keeping it that way for it's anti knock ability and putting more timing into it. I am running the flex fuel kit so I can easily switch between gas and ethenol where ethenol is sparse. I would recommend the highest ethenol percentage wherever possible but just my 2¢. Mixing is a waste of time unless you are over 350hp where duty cycles on the injectors get higher
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I am indeed still running a straight mix of e85. My tuner is very good at his job, and suggested keeping it that way for it's anti knock ability and putting more timing into it. I am running the flex fuel kit so I can easily switch between gas and ethenol where ethenol is sparse. I would recommend the highest ethenol percentage wherever possible but just my 2¢. Mixing is a waste of time unless you are over 350hp where duty cycles on the injectors get higher
It has been shown time and again that running full e85 is not ideal for our cars as you will get fuel pressure drops. To run e85 full you then have to run lean AFR like 12.1 and higher. I would love to see what AFR you are running at WOT on full e85.
 
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It has been shown time and again that running full e85 is not ideal for our cars as you will get fuel pressure drops. To run e85 full you then have to run lean AFR like 12.1 and higher. I would love to see what AFR you are running at WOT on full e85.
As a reminder, I live at 6000+ feet above sea level and my ambient air pressure is much lower than that of sea level. I am only reaching between 19 and 24lbs of boost. So I am getting nowhere near full duty cycle nor should there be any fuel pressure drops that would effect my performance. At least after 5-6 Dyno passes in 4th gear between 2.5k and 6.6k rpm there was no noticable drops in pressure or spikes in injector duty cycles.

Could you point me in the direction of these fuel pressure drop instances though? A fuel pump should be pumping fuel the same whether it is gas or ethenol as the viscocity are very similar between the two (.0006 poise for gas and .0003 for ethenol) and if you take the mix of ethenol and gasoline that I have (65% ethenol 35% gasoline) we can solve that the viscosity is somewhere around .00045 further increasing the viscosity to that of gasoline to where pressure should be at least close to the same.

Thanks so much!
 

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Well according to a few tuners like @D-RobIMW there are lots of issues with running full e85, Ill post a couple of screenshot but honestly they could explain it better. Not sure how altitude affects the use e85, I know it messes with your boost.

Honda Civic 10th gen Straight e85 on an ex-t upload_2019-2-25_10-36-42

Honda Civic 10th gen Straight e85 on an ex-t upload_2019-2-25_10-36-52
 

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Well according to a few tuners like @D-RobIMW there are lots of issues with running full e85, Ill post a couple of screenshot but honestly they could explain it better. Not sure how altitude affects the use e85, I know it messes with your boost.

upload_2019-2-25_10-36-42.png

upload_2019-2-25_10-36-52.png
That makes a lot of sense. Based on a limited window, you don't ever get to use the full duty cycle range of the injectors because of a late starting window. Even if the LPFP, HPFP and injectors have the capacity to move the fuel, the software is keeping you from using all that could be provided.

I'm pretty sure when I was looking at some part #s on another thread, it looked like all the trims were using at least the same HPFP and I thought injectors as well. I'd have to look back and make sure I'm not all screwed up on it... but if it's all the same, and I keep hearing the Si's have more fuel capacity than the other trims, I wonder if it's just software induced.
 


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That makes a lot of sense. Based on a limited window, you don't ever get to use the full duty cycle range of the injectors because of a late starting window. Even if the LPFP, HPFP and injectors have the capacity to move the fuel, the software is keeping you from using all that could be provided.

I'm pretty sure when I was looking at some part #s on another thread, it looked like all the trims were using at least the same HPFP and I thought injectors as well. I'd have to look back and make sure I'm not all screwed up on it... but if it's all the same, and I keep hearing the Si's have more fuel capacity than the other trims, I wonder if it's just software induced.
Im 99% certain Derek said the SI is different than the others.
 
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Well according to a few tuners like @D-RobIMW there are lots of issues with running full e85, Ill post a couple of screenshot but honestly they could explain it better. Not sure how altitude affects the use e85, I know it messes with your boost.

upload_2019-2-25_10-36-42.png

upload_2019-2-25_10-36-52.png
Thanks for that! Yeah, so it all makes sense, your not losing fuel pressure and essentially you are closing the window at which fuel can spray by using direct injection. Although, here at elevation we have a ambient air pressure of ~11.8-12.5 depending on the temperature. And as you already know less air = less fuel. And as we saw zero risk when tuning we had no problem running full winter mix e85 (65%). The more ethenol you have the less risk of pre-det, knock or overheating and so we saw fit, at least for my car in my situation, to run a full gas station mix of ethenol.

Does that make more sense?
 

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Hey guys, I know a few we're asking about times to show the power of the car... I'm not a huge 1/4 mile guy but I love time attacks and road racing.

I hate I told you so's but y'all can sock it to me, I had to bump my ethenol content from ~65% to 55% due to a slight bit of leaning out under peak torque. It would hit somewhere around 11.8-12.0. Nothing catastrophic but enough to make me say "oops"

To give an idea of how the ex-t did (a lot of these things have to do with driver more than anything) a stock civic si ran 48.5 seconds, type r went 46.0 seconds. My EX-T on 255/45/r17 bfgoodrich pro comp 2 tires making 342lbft and 255hp went 47.2 around the track while spinning on almost all on the sweeping corners and through the slower straights.

Sorry for the data being fairly skewed and not consistent with what you guys probably wanted, however I had an absolute blast. A LSD probably would have done wonders around the sweeping corners.
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