I've gotten a few PM's lately asking about my car and more specifically how to e85. I have some reservations about telling someone how to add e85 when my knowledge is there but is still pretty limited. I decided it was time for a blog post with my experience using e85.
MY goal using e85 as I wrote on my blog, make California's crappy 91 octane gas a little more palatable to the car, increase the octane rating. Some posts say it doesn't, some say it does. What's the truth?
Here's a little gif (not JIF) I made showing the difference in timing corrections on the MHD beta when using...
Just 91 octane:
[IMG]https://i0.wp.com/*************/wp-content/uploads/2018/02/noE85gif.gif[/IMG]
And using 91 octane with a little E85 mixed in:
[IMG]https://i0.wp.com/*************/wp-content/uploads/2018/02/E85timinggif.gif[/IMG]
Same car, same tune, same mods, 10º difference in weather, much better timing, does the above prove e85's ability to perform as an octane booster?
Link to the blog post
Back at it, I've bounced the post off a couple people, received some thoughts and knowledge but would really like some place to discuss the various things going on when using e85.
I understand I may be complicating something simple but there's a lot going on under the hood and having a deeper understanding really peaks my interest.
There are so many posts out there on all the forums regarding e85, how you should and shouldn't use it, how it's awesome, how it's the worst stuff ever, etc... It would be nice to have some data, some facts, some real life experience, etc.. in regards to using e85.
I was hoping to have an open discussion here about your thoughts and experiences on e85 usage.
What to look for in logs when spiking your tank with e85?
Timing, fuel rail pressure, and other logging parameters?
Ethanol maps vs higher octane maps when using e85, etc..?
Measuring ethanol content?
Your experience with e85 blends (As the .gov guidelines seem pretty variable)
Summer vs winter blends, etc...
To start things off, I was curious how one would determine if they were using to much e85.
Someone (Thanks Joseph) in the MHD beta chat was courteous enough to explain that a potential sign in logs of using to much e85 would be your
rail pressure mean psi (aka
FP_H in the JB4 world) dropping below 1600 PSI.
At first I didn't get it, to me it seems counter-intuitive, I would just assume the rail pressure would get to it's highest PSI rating and just not produce more power because it can't pump anymore, but I was wrong.
Because e85 doesn't have as much energy as gasoline the injectors... inject more fuel and as a result of that, the rail pressure drops because the fuel pump can't keep up with all that extra fuel flowing out.
I hope I'm not the only one that didn't know that but yea...
Thanks again everyone and looking forward to learning some stuff.