DA 4 Lyfe

I'm going to be getting tuned with E70 for the early spring months but plan on throwing in the legit E85 once the summer blend comes out. My question is will I only have to change the fuel maps to support the higher reading content?

DA-NINE

To optimize power potential you should return whenever your octane rating changes. I'm sure going from a lower octane to a higher ocrane shouldn't give you any issues but a return will let you utilize the extra octane count.

Also you could get a gm ethanol sensor so you will have rolling fueling and timing adjustments after its tuned so you won't have to switch tunes (if your ems supports it)

DA 4 Lyfe

Playing it safe with pump E85 is not a bad idea IMO. My main concern is that I won't run into issues from being tuned on E70 and then using the E85 when the summer blend comes out. If the only thing that will need attention are the fuel maps, then I can take care of that by doing a little data logging on the street my self.

As far as engine management I am running a Hondata S300 V1. I don't think it allows it to work.

A flex fuel sensorsounds like a great idea, but is it really necessary to purchase one if the only thing that changes will be the fuel? I'm new to this whole E70-E85 idea

4drEF

It's not required, but it does offer some features that you may find useful.
Tuning with the ethanol sensor is done at several points. You do tunes with your low octane, high octane and then mixtures in between.
If you had a street car that would use E85 for track days, then maybe you would have 91 octane and E85.
After your 91 tune, you drain the tank and put E85 in and tune again. Then you add some of the 91 to reduce to lower ethanol content - maybe E60 - and tune again. Now you have all these data points for different ethanol content in your fuel.
If your fuel degrades or you buy different ethanol fuels, then youI are covered. No need to mess with the tune just because you changes fuels.

wantboost

iTrader: (2)

I don't like how the s300 does ethanol compensation. It's not true flexfuel.

It only compensates a preset value for fuel and timing based on ethanol content.

Other EMS like the AEM EMS, Infinity, Megasquirt 3 pro, etc all read an ethanol content sensor and actually blend both timing and fuel maps, no compensation only, based on ethanol content. You need only tune for your e10 pump gas and e85, the ecu does the rest.

The cost of entry might be a bit higher for a standalone but the ease of use and powerful features and best endless adjustability make them a far better solution for high power complex setups. I'm sure a few other members will agree while the rest won't lol.

Also remember that summer e85 is rarely 85% ethanol, same for the winter e70. To determineif your current tune is accurate (I would be more concerned about timing than fueling personally) you really need to test both the e70 and e85 from the station(s) you use regularly to get a feel for what actual ethanol content is how "regular" the purity is as well as the actual ethanol content difference between the two.

If the purity stays fairly consistent but there's a big gap in ethanol content between the two thenI'd say a retune is the safest route. You have to think about what costs more... A retune or building a new motor?

Also if you plan on running ethanol regularly then I would seriously think about getting an ethanol content analyzer. Even if your ecu doesn't support flexfuel it will still allow you monitor actualethanol content inrealtime . This is not only beneficial for the health and performance of your motor but it will help you avoidstations that might have a recurring ethanol content problem or when the ethanol content in your tank is drastically different then what you were tuned for.

That's just my opinion

DA 4 Lyfe

I'm not to worried about having a real aggressive Ethanol tune, that's why I'm still going to be tuning with C16 for the track. I figured if I have a semi conservative Ethanol tune to drive around town with then all ill have to worry about is adding fuel. I have a Ethanol test tube, not sure how accurate they are but it's at least a piece of mind right? Once the summer blend E85 comes out to the pumps I will just have to do some street data logging to nail down the AFR's

wantboost

iTrader: (2)

Yea I mean it's not so much that your tune is aggressive, you just need to be sure that it's conservative enough that big changes in ethanol content from tank to tank won't cause issues with performance or engine health.

The tubes are great for measuring at the pump but the sensor will tell you real-time actual ethanol content. Keep in mind that if you fill up on anything less than an empty tank that you're going to be blending content percentage with whatever is left in the tank. Also remember that ethanol absorbs water like a sponge which can also lower ethanol content.

As long as you keep a conservative tune and occasionally test ethanol content when filing up I don't foresee you having any issues. If at some point in the future if you want more power or a more powerful/easier way to tune then a standalone that supports an ethanol content sensor and real time map blending would not only run better but it would remove any doubts about your tune being impacted by ethanol content.

DA 4 Lyfe

Right now I have a Hondata s300 Version 1 so I'm pretty sure I can't do anything other then add a flex fuel sensor? Within the next year I do plan on upgrading to a AEM V2 EMS. Will that adjust the tune to the fuel % from winter blend to summer blend E70/85?

I am getting tuned in March with my new fuel system and its a little over 3 hour ride down to CMR.. if my tuner was local I would just wait for the summer blend E85 to come out but I'm kind of limited on time. It's sounds like I might be in pretty good shape with just getting tuned on E70 and keeping the timing conservative and just make changes to the fuel maps in regards to when I start using E85. I will just keep testing it before I gas up at the pump and start using the E85. I was never a Flex fuel guy but with my new fuel setup i figured she would be plenty good for E85