Flex Fuel ECU DSM...?

[Boug]

Hello all. Based on the latest news in the GTR world, I was wondering about the possibility of this becoming an option for the DSM platform.

Worlds first flex fuel factory Ecu GTR! - evolutionm.net

I know that this has been discussed in the DSM realm at length but I am not sure if there was support to invest the money by a company in a platform that is knocking on the 20-year old door.

The closest I have seen for the DSM platform is this: http://www.dsmtuners.com/forums/bolt-tech/345925-full-flex-fuel-conversion-kit.html

E85 Conversion Kits Change2E85.com

As for the EVO, I am not sure that this "on the fly" capability has been mastered. The only thing I know of is "map switching" but nothing to take into account the variances with E85 through the ECU. I believe there is enough demand for the EVO 8/9/10 but whether or not EcuTek (as it seems they have monopolized this capability) is looking in that direction. The question that I have is whether or not this capability can also take into account when you "have" to use non-E85 fuels and still be able to compensate the tune. My guts says yes as you will just be at a much lower E85 content level in the tank. My follow-on question (considering my first question is true), is whether or not it is possible to have a non-E85 tune that is still pretty good.

I am interested to see (read) each of your responses.

 

[snowborder714]

There's been some discussion of this (on-the-fly changes based on logged flex fuel sensor) on the link forums, but it's been deemed too expensive for them to take the time to develop. The sensors are $300+ and most people probably won't want to spend that much on it when they can just open a laptop, switch a few settings to get CombinedFT back in check, and go. It's something they'd be open to consider if either enough people would want in on it or if sensor prices drop to something more reasonable.

I think it'd be cool to have, but more of a "luxury" than a necessity.

 

[c2ypt1c]

Are you talking about dynamic fuel compensation, or dynamic maps (timing, afr, etc)? The former being pretty damn easy to do manually as Tom already mentioned in this post:
http://www.dsmtuners.com/forums/152024812-post2.html

The process takes a whole 10 seconds

Dynamic maps based on ethenol content, however, would take a lot of work and I doubt it would ever be introduced. I also doubt that's what's happening in the video you posted. I suspect the ecu is just adjusting for fuel compensation.

That said, all you really need are two "tunes." One for pump, one for e85. Anything lower than a 50/50 mix, I'd use the pump tune; higher, the e85 tune. I personally use a 50/50 mix for my full e85 tune, just so I have some sort of limitation in terms of timing advance and knock retard. That's just me though...

 

[Boug]

Apparently, the ECU "automatically adjusts" based on the amount of ethanol present. It also seems as if each map is dynamic. I know about changing maps via a laptop between E85 and pump/93 but the one thing that has always been a concern of mine is for example, being tuned on E85 and then in the winter months only having E75 at best and still believing that your tune is safe when actually you are more viable to cause damage due to the differences between E85 and E75. I guess "a way" is to "guestimate" how much is being left on the table with an E85 tune to compensate for the variations. I posted this here to get opinions on this technology.

 

[livedsm4g63]

That is one reason why my laptop always rides shotgun.

 

[c2ypt1c]

It also seems as if each map is dynamic.

What makes you think that? If this were the case, I'd say that's pretty impressive.

the one thing that has always been a concern of mine is for example, being tuned on E85 and then in the winter months only having E75 at best and still believing that your tune is safe when actually you are more viable to cause damage due to the differences between E85 and E75.

If your car is properly tuned, I would not worry about this at all. Your timing should not be so maxed out, on the bleeding edge, that e75 causes problems.

 

[bastarddsm]

Allready have it in my car. Testing it out in my dd GGSX. It's not ecmlink or anything. it's a custom rom I made.

 

[Boug]

What makes you think that? If this were the case, I'd say that's pretty impressive.

The creator of the capability made the statement which is why it is impressive for the GTR powerplant.

If your car is properly tuned, I would not worry about this at all. Your timing should not be so maxed out, on the bleeding edge, that e75 causes problems.

OK. I understand what you are saying.

What makes you think that? If this were the case, I'd say that's pretty impressive.

The creator with EcuTec stated it as being so.

 

[bastarddsm]

Going from E85 to E75 won't really cause problems. You just don't make as much power. I've noticed about a 5% loss

 

[Boug]

Allready have it in my car. Testing it out in my dd GGSX. It's not ecmlink or anything. it's a custom rom I made.

This is great, my friend. The thing that comes to mind is although it is a single .rom file, but that does not speak to the ability of the ECU to "adjust on the fly" to compensate for changes within E85. But like another member that posted here, maybe it is all smoke and mirrors as it really is no threat to an engine between E70-E85 basically.

Going from E85 to E75 won't really cause problems. You just don't make as much power. I've noticed about a 5% loss

This is very good to know. I am learning more every day.

 

[c2ypt1c]

The creator with EcuTec stated it as being so.

Do you have link (or other resource) or is this just hearsay?

 

[Boug]

Do you have link (or other resource) or is this just hearsay?

It can be found at: GT-R Life - NAGTROC - MEGTROC - SGGTROC - GT-R Life.

 

[donniekak]

Proefi already does this.

 

[11secDSM]

Proefi already does this.

So does AEM and MOTEC. I think they're just referring to stock ECU capabilities.

 

[bastarddsm]

so does a mega-squirt.

Here's my biggest issue with the whole thing. I know how I do it, and I know how mega-squirt does it.

It has a linear interpolation between two timing maps, but I don't think that timing vs ethanol content is a linear function. Meaning you set optimum timing at E0 and E85, and it's linear between, so you end up with most likely too much timing in the mixture areas, or hopefully, not enough timing.

Anyone know what the advance vs E% curve looks like?

Fuel wise I don't think it's that big of a deal. I really think e85 likes the same ish AFR's as gas, so just scaling the globabl injector comp works for me.

 

[c2ypt1c]

so does a mega-squirt.

Here's my biggest issue with the whole thing. I know how I do it, and I know how mega-squirt does it.

It has a linear interpolation between two timing maps, but I don't think that timing vs ethanol content is a linear function. Meaning you set optimum timing at E0 and E85, and it's linear between, so you end up with most likely too much timing in the mixture areas, or hopefully, not enough timing.

Anyone know what the advance vs E% curve looks like?

Fuel wise I don't think it's that big of a deal. I really think e85 likes the same ish AFR's as gas, so just scaling the globabl injector comp works for me.

Exactly! I completely agree

 

[AK Maniak]

As nice as that could be for some that just seems like something that will never come to this platform for no other reason than DSM'ers being to cheap. I don't blame ECM for not developing this. When you still have some people going with an SAFC over DSMLink I doubt that there are enough dsm owners who would be willing to spend the extra bit to get this feature.

 

[c2ypt1c]

As nice as that could be for some that just seems like something that will never come to this platform for no other reason than DSM'ers being to cheap.

I really don't see a benefit, aside from being able to switch fuels without a laptop being present. That's about it...

 

[MY1GDSM]

I've been too busy to get around to it yet but In the next month or so my 1g will be a true flex fuel vehicle. I'm more or less doing it just to do it. I rarely run gas but the Idea of making a road trip an not having a second thought about pumping a mix in is appealing...

Just debating on paying for a $200 frequently convertor or building something though the Idea of a nice read out of the content is nice alone. But with the newer gm ffv sensor only around $70 vs the $300+ they were. it's a bit more practical any more. I'd get into this a bit more but I'm on my phone atm...

 

[donniekak]

so does a mega-squirt.

Here's my biggest issue with the whole thing. I know how I do it, and I know how mega-squirt does it.

It has a linear interpolation between two timing maps, but I don't think that timing vs ethanol content is a linear function. Meaning you set optimum timing at E0 and E85, and it's linear between, so you end up with most likely too much timing in the mixture areas, or hopefully, not enough timing.

Anyone know what the advance vs E% curve looks like?

Fuel wise I don't think it's that big of a deal. I really think e85 likes the same ish AFR's as gas, so just scaling the globabl injector comp works for me.

What pin are you running the ethanol sensor into, and what sensor?

 

[bastarddsm]

EGR pin, I use a Freq to voltage convertor off the GM FFS.

I have a whole lot of cool shit done to my bin/rom.

I've been too busy to get around to it yet but In the next month or so my 1g will be a true flex fuel vehicle. I'm more or less doing it just to do it. I rarely run gas but the Idea of making a road trip an not having a second thought about pumping a mix in is appealing...

Just debating on paying for a $200 frequently convertor or building something though the Idea of a nice read out of the content is nice alone. But with the newer gm ffv sensor only around $70 vs the $300+ they were. it's a bit more practical any more. I'd get into this a bit more but I'm on my phone atm...

When I first got it going, I used a 10k pot hooked to 5v, and just tuned it so my car went to the right AFR at wot. Pretty easy.

 

[mike96]

This may be something read. From the looks of it (at least on the EVOecu side of the house) it is a lot closer to being a reality.

FreeFuel ECU patch - a flex fuel implementation to Evo ECU - evolutionm.net

 

[goodhart]

This may be something read. From the looks of it (at least on the EVOecu side of the house) it is a lot closer to being a reality.

FreeFuel ECU patch - a flex fuel implementation to Evo ECU - evolutionm.net

This is what I was thinking of when I clicked on this thread. Guys that have swapped to Evo 8 ECU's should be able to implement this. This should be nice for people that make long trips and have to fill up with pump gas where e85 is not available.

Otherwise, from my experience, having the car tuned at ~12.0 afr on e85 yielded ~11.2 afr's on e70. I usually just let it run richer in the winter months, it won't hurt anything and was about a 10-15hp difference on a Dyno Dynamics.

 

[AK Maniak]

I really don't see a benefit, aside from being able to switch fuels without a laptop being present. That's about it...

I personally wouldn't need or want it and I'm assuming most DSM owners wouldn't either but that could be because most of us tune everything our self.

Where as on EvoM most a lot of those guys pay a shop to build and tune their cars. If I had a shop built and tuned evo I wouldn't mind paying a few extra hundred bucks to not worry about what kind of fuel I put in it.

 

[donniekak]

EGR pin, I use a Freq to voltage convertor off the GM FFS.

I have a whole lot of cool shit done to my bin/rom.



When I first got it going, I used a 10k pot hooked to 5v, and just tuned it so my car went to the right AFR at wot. Pretty easy.

I'm not going to ask for any detailed info about your .bin. But, I do have a question. Did you use the stock hi/low octane maps, and use the flex sensor to interpolate between them, or write code for extra maps?