Well I was going to go pure 93 but in a few months I'm going to have another daily so this one will be a fun car on the street. With that said I will not be taking it on long trips and can run it on E85 if I want. What I want to know is, is it worth going for E85 if you haven't maxed out 93 octane? Or does E85 only make sense once you ran out of pump gas octane per power?

 

Personal preference decision. Subjective stuff like this can go in no direction, really fast. Lol! However, E85 is a pricey choice, given that it takes about 40% more fuel to make power. Availability can also be an issue; i fall into that category. Lol! That's why I went with the water/methanol injection. If you add the costs of setting up for a flex fuel system, I strongly believe the water/meth kit is a lesser expensive route than making your power solely on E85. My final HP was 369.9 and my injector duty cycle was only at 42% on 93 octane. 750cc injectors.. I have PLENTY room in the injectors to play with, for sure.

 

The other thing to keep in mind is how E85 holds moisture. You really need to either be running through it consistently, or draining and flushing the system with 91 before it sits.

 

power for power, you will ALWAYS MAKE MORE power on E85 than pump gas. It's just a matter of tolerance, preference and availability. Some areas, the local gas stations don't carry E85 and that deters people away from it.

For me, I don't drive mine that often so I'm like whatever. The nearest BP that has E85 is about 15 min drive away so I'm not bothered by it.

 

Hmmm that doesn't sound good. And I won't be driving this car much.

 

You add some extra timing when using e85 and it’s a colder fuel which which make some extra power, just might need a little extra maintenance in the long run..... no brainer for me or anybody trying to make a lot of power or safer power

 

If you have E85 available, I'd either set it up for E85 or set it up for flex fuel. Flex fuel is a little more up front cost, but it's super nice to run E85 all the time, but have the option to put in some 93 octane if you can't find E85, and not have to worry about draining the tank to switch over or booting up the laptop to throw in your emergency pump gas tune.

 

When I did my searching before posting I read that Flex fuel on Hondata isn't that great of an idea. I read it works much better with AEM. And I have quite a bit of E85 stations local to my house.

 

Curious what you read about using flex fuel with Hondata? I haven't had any issues so far.

 

https://honda-tech.com/forums/forced...-fuel-3245693/

 

that's a 5-year old post. Hondata does blend tables now and last year they rolled out ethanol content based boost compensation. I can literally have a half tank of E85 and put in 2 gallons of 93 and do nothing - the computer compensates fueling, timing, and boost levels accordingly.

 

I might go the flex fuel route then. I am a little worried about hearing the E85 and moisture though... What are you guys doing to combat that?

 

Alcohol based fuel tends to be hygroscopic in nature.. That's really over extended storage time though. Best to drain and flush the fuel system before putting her up for winter time if you do that kinda thing. Of course, you don't wanna store even regular gas for long periods for the same reason; condensation. Best to either fill or drain the tank completely before long storage. The larger problem with ethanol/methanol is that it is REALLY harsh on rubber fuel components and some metals. Also has the tendency to turn into a congealed mess. Lol!

 

make sure your fuel components are compatible with E85 is the first step. Next, if my car is going to be down for more than a month, I drain the tank as much as I can and fill it up with 93 octane, then if possible, let it run for about 10 minutes to circulate the gas through the system. I clean my fuel filter (20 micron stainless steel) about twice a year just for good measure. That's it.

 

Nah. 93 is too easily available. I could also make my own methanol mix

 

93 way less headache and you dont have to plan your trips

 

It's really more for "safer" power. Ethanol doesn't quite compare to pump 93 in the typical sense.. It takes more ethanol to create that power. In other words, you're making 400whp on gasoline, you'll need AT LEAST 40% more ethanol to make that same power. The trade is that you're allllmost eliminating knock factor with the ethanol. Not sure if that's been covered yet.. **shrug**

 

How far power wise will 750cc Grams injectors take you on E85?

 

This is a good nuance to mention for those not familiar

 

about 350whp on 750cc running E85. You'll need at least 1200cc to get you to 400whp and 1600-2000 for 450-500. 1000-1200cc will be ok for upward of 500 on pump 93. 1200 to play it in a more comfy DC range. Add methanol spray to that and you'll be amazed. I made damn near 400 on 93 with 70/30 methanol/water spray and only hit 48% duty cycle on my 750cc injectors. Had to dial it down though cause of clutch slippage up top.

 

I pegged my PTE 1000s at 450whp ish on E85 with a Walbro 255

With a Walbro 450 got that to 567 upping the base pressure

Keep in mind these injectors were way higher then recommended DC lol.

With 2000's at 630 whp it was a bit more comfortable @ 70% DC

 

I actually did a test with E85 as a daily driver about a decade ago. When I ran my Civic at about 500whp on the streets with AC/PS I got close to 27MPG on pump gas. I actually went out to AZHT and looked back at the post I made in March of 2010 below:
Also unless you are planning on not driving the car for months at a time then yes I would suggest draining the fuel and running pump gas through the system to clean your lines, pump and injectors. 1000cc injectors can get you 500whp no problem, I've actually done more than 600whp, 2000cc injectors can get you around 900whp anything above that which I am sure is not your plan you would need 8 injectors.


Ok here are the results for my miles per gallon test

I got 261 miles on my tank of E85 and that wasn't ***** footing it either.
70 mile an hour average on freeways, getting in and out of boost many times.

So here are the breakdowns.

11 gallons in my car to start

261 miles / 11 gallons in the tank= 23.72 MPG on E85