You can miss the blend ratio by 10% and only shift the fuel trims 3-4%.

Here's a blend & octane calculator, but E47 is 1:1. When mixed with 93, E47 is 99 octane.

Ethanol Calculators

 

That's the same link I posted a couple posts ago..

 

i run E85 fully bolted....made 339/352 (Trifecta 21psi tune)...ill be switching to E47 hp tuned with the Zfr until i can get the cam then its back to E85

 

I know when css3 tuned me for e47, he keeps it in a safe area for that reason. Cuz when i first went to e47 it i would get more of one fuel over the other. But ive never had an issue when i was learning how to mix, lol.

robk

 

Thanks guys. Will be looking into this once my wastegate is tightened.

 

If you are dialed in for e47 and accidentally run either something like an e42 or even an e52 blend, it's really not a huge deal. It will no doubt throw your trims off, but it should still keep you in a "safe zone" to not have to worry about them going crazy one way or another. For example: an e42 blend will cause your trims to fall in the area of around -3% to -4% range and an e52 blend will cause your trims to raise in the area of around +3% to +4% range when dialed in for e47. It's obviously not perfect but a +/- 3% swing is still considered safe and shouldn't cause any harm to the car.

You still should be monitoring your blends though and never ever assume what the ethanol content is.

 

I have a few questions about running E47.

1. Will I have to drain the tank completely the FIRST time I want to run E47? Then just fill it up with 6 gallons of E85 and 6 gallons of 93/91 after the tank is completely drained? Or can I somehow leave my existing 93 in the tank and then add the same amount of E85 to get my E47 mix?

2. Do I do this before I drive my car to my tuner so he can tune it for E47? I'm on a stock tune right now, but we'll be going with a HP dyno tune. Basically I'm asking this, can I drive my car about 50 miles (to my tuner) with E47 in the tank without being tuned for it?

3. Can I test the Ethanol right at the pump with that tester to be sure it is 85% E or will I have to put it in a 5 gallon tank and test it at home to make sure it isn't only say 70% Ethanol which was mentioned that can happen depending on the station, time of the year, etc?

09CobaltSS1, I'm sure you can answer these for me

 

lol.. Does that mean I have no choice in the matter?

1) You really have a few options here. You can; A) run the tank to almost empty with 93 to ensure a pretty nuts on blend to start with, B) Make an educated guess using the "rough estimate" method that basically each 1/4 tank full on the fuel gauge is roughly 3 gallons of fuel method (1/2 tank is roughly 6 gallons of fuel for example) and add that same amount of e85 (this has always worked quite well for me actually) or, C) If you have access to hptuners, just add the "tank level gal" pid to your table and see how much is in your tank that way, and make your blend accordingly. Just be sure to know exactly what blend of ethanol is coming out of the pump to start with before making and blend calcs to begin with.

2) I would absolutely NOT drive your car that distance without having the tune compensated for previously. The fuel mass needs to be compensated for in the tune before hand, otherwise you run the risk of leaning out. Yes, the trims will do their job as best they can, but you're playing with some serious fire going that route.

3) I would absolutely 100% recommend testing ANY e85 that comes out of the pump before it enters your tank. You want to do your best to ensure a consistent blend each and every time you fill your tank. If the final blend in your tank is a few % off in one direction or another, it's not really a huge deal particularly in a LNF due to the simple fact that our ecm's work on a full time closed loop system even at WOT. This basically means that the ecm can constantly monitor and adjust fueling accordingly even at WOT. Even so, you still want to keep your blends as consistent as humanly possible.

 

Your the man! Sounds like I'll have to talk to my tuner once the time comes and see how we wants to go about it. I guess I could just have the tank low on 93 and bring the car to him with two 5 gallon cans, one full of 93 and the other of E85 and he could pull it up with HP tuners and go from there.

 

What is the ethanol content for e85 winter blend??
Can you run e85 winter blend on an e47 tune??
I've read that it can take some gas stations until May before they begin selling a summer blend of e85.

What i guess im asking is would I just have to run a blend heavier on e85 say a 1.5:1 ratio for example or do I have to wait until the summer blend is available??

Thanks fellas.

 

It all depends on the specific station more so than the time of the year really. The station I use has e85 all year round, however I've tested ethanol content at a station a few towns over in the middle of July and the content was only 70%. Always test content before making your blends is what it comes down to.

 

Ok thanks.
I know this may be repetitive but I just want to make sure I've got this right.
You're saying that as long as I've tested the e85 I can blend it accordingly in order to reach my goal of e47 correct??

 

Also should i blend with 91 or 93??

 

Yes, you must see what % of ethanol you're starting with in order to make an accurate blend. Otherwise you will end up with anywhere from e40-e47. That much of a disparity will **** off the tune.

 

You mine as well use 93

 

Thanks man.
I just ordered a tester off of ebay a few minutes ago.

 

I use the tester 09CobaltSS1 recommends from Summit Racing. It's pretty sweet. Just make sure to wait like 10 minutes once you mix it in the tester as it takes a little bit to settle.

The station I use has had e85 all year around so far since I converted... so that's the one I go to. Not that I have to many other choices anyways

 

I ran E47 for well over a year and a half with zero issues and i not once ever tested the e85 content. I would fill up between 3 different stations, thortons-who had a minimum 70% ethanol content, Meijer-who also had a minimum 70% ehtanol content, and Speedway-who had a minimum of 50% ethanol. If i went to Speedway i usually just added more e than i would 93 to offset the difference. But like i said i never tested and had zero issues and the car ran fine and strong.

robk

 

Good for you.. Lol

They guarantee a minimum of no less than 70%, doesn't mean it is 70%. Blindly guessing is never smart when it comes to this sort of thing but to each their own.

 

Wow what a way to be an ass, no wonder people dont like to get on here anymore.

I was merely giving my own personal experience so that incase someone was intimidated or worried about "blend ratios" and such, that a good tuner will set a safe parameter in the tune, no matter the ethanol blend is at the time.

And yes i am aware that just because they "claim" a certain percentage doesnt mean thats exactly what it is.

But thanks for your pointless comment.

robk

 

Robk- John might be a little blunt, but he brings up a valid point, that being fueling requirements. If your tuner is trying to somewhat get the most out of your hp motor he should have based timing and fueling on a certain mix. It takes roughly 13% more e47 fuel, to equal 93 octane gas in efficiency, and feel free to correct me if im wrong, as im a big boy. The benefit with e is increased octane ( roughly 99 octane on e47), which im sure you know. If your taking advantage of running 98-99 octane for what its designed for, you will increase your timing. If you end up running something like e-35 due to the e being low, with your tune set to timing levels of e-47, the less than 98 octane can put you into pre detonation, or knock, which eats non forged piston engine's, and isn't good on engines in general. If your tuner did like you say, and didn't increase timing alot, its kind of pointless to run e. I am not a expert, just an older hot rodder whos been into cars along time. You also would probably be running a little rich if your running e-35 with fueling set for e-47. Just my 2 cents.
Thanks for sharing your experience with us, its nice to know that there is some flexibility to running it.

 

Nova, i realized i might have been harsh by my initial comment for which i apologize to John. I've never once done or said something like that in my 3 years of being on this site.

But yes as far as i can remember my timing was in the range of 24-25* in the mid-range and 26-27* at top, on a 25lbs.

As far as the octane of e47 i was under the assumption that it was 100+ octane, but i could(and probably am) assuming wrong, lol. From what i had read on this site before i went to e47 (i believe it was Iam Broke's tests on blended fuels) is that basically from e30 to e47 there really wasnt much of a difference in the actual octane and the benefits was minimum at least, and yes i tryed searching for his test post, lol. Yes i am a forged piston car, but i experienced zero knock during tunning nor during daily driven status. And yes i have a MSD Dashhawk for monitoring such things.

But like i stated above, that my own personal experience while running e47, and it was merely a statement for those that are unsure on the whole testing aspect of the blend.

Thanks
robk

 

anybody got pumps like this one??
Haven't used it yet but I'm sure it'll be better than pushing my car between two pumps haha.

tested the e85 at my local pump and my tester reads 80 so I guess I'll pump a little more e85 in the tank to get as close as I can to an e47 blend.

 

looks like the ticket, and no pushing!

 

I don't test either...
Going strong after 4 years of E47.
It's not rocket science, doesn't need to be right on.

With E25 thru E85, you have enough Ethanol to suppress any knock,
& won't have any problems with your E47 tune, if the mixture is off.