E85 Fuel Consumption

[Dose Pipe Sutututu]

fuel compensation table 

[Kinkstaah]

And fuel compensation scalar. It basically defines how much of the fuel compensation table is applied.

Note: It is not linear!

[No Crust Racing]

[Dose Pipe Sutututu]

the scalar is interesting.. at 80~90% of ethanol registered it should be 100% of the compensation table, yet you tuna has used 133%

Meaning it would be your base tables + 1.3x of the compensation table applied on top for fuel.

Hopefully the timing table isn't like that, because well... it's an interesting way to tune.

[No Crust Racing]

Your turn to post a screen shot then.

[Kinkstaah]

Also 44% more fuel is massive, 133% of 44% more fuel is obscene. The numbers just look... wrong?

The stoich values of 98 and E85 are too different surely for both the 98 tune and E85 tune to be right at the higher end of that scale. Either the 98 base tune is dangerously, dangerously lean, or the E85 is horrifically rich.

Now keep in mind, if you have the O2 sensor running and the controller doing its thing, it is possible for these correction maps to be really far out, and the O2 controller will do what it can to adjust. This may be the reason the car has bad E85 economy if it cannot actually trim enough up top. What is your AFR under load on E85 anyhow, what does the Haltech say/does it show in the onboard logs?

[No Crust Racing]

Not sure without going doing specific diagnostic runs.

I've got a mate coming over tomorrow who will want to go for a spin so can take the laptop and upload a trace then.

That said i think we established that my economy was about the same as others here.

I have a trace from winton but the car had a phat boost leak.

[No Crust Racing]

Just spoke to another local tuner and showed him those snaps and he said the same thing about it being unusual but could be fine depending on the rest of the setup.

He's happy to have a look at my log after I get one.

Will go from there.

[Dose Pipe Sutututu]

It's interesting to say at the very least, I personally don't tune like that.

I'll provide screen shots of a S15 I did about 2 months ago with a halaltech when I'm home.  I personally did not follow the same approach as your tuna.

[No Crust Racing]

They call me the postman, because I always deliver...

https://expirebox.com/download/a700385dce0e228b3426cb2b28ae741a.html

Diagnostic csv from a quick run down the highway and back today.

Only 2MB, file expires in 48hrs. 

[No Crust Racing]

Was looking at the trace and noticed that there was no wide band data, because that channel doesn't appear to be selected for logging by default 0_0

 

 

[Hadouken]

If only you had an AFR gauge

[No Crust Racing]

"Yeah I floored it and it was like 9 or 10 or something around full boost, or there abouts, yeah between around 4 and 5k rpm" 

Would have been heaps accurate and a great way to do some logging lol you muppet

Then you'd be the first person jumping on to say "You should have logged it properly." 

You must be a blast at parties lol

[Hadouken]

Your words, not mine.
I don't care about logs.

If those afrs are real then that's richer than an arab

[No Crust Racing]

What you do care about besides being salty all over SAU lol 

I'm confused, why did you and are you still posting in this thread anyway? 

It's cool if you like me dude, we can take it to PM  


 

 

 

 

[Hadouken]

Well looks like that's the way you want to be then.

Lol, says a lot seeing as you pm me for help.

Ah well.

[No Crust Racing]

Help? Do you mean asking your thoughts about your Evo? Or talking -9s and response etc? Not sure if I count opinions as "help", but then again you are helping by answering and giving me your thoughts so I guess that's a fair point of view from a certain perspective - if that's what you mean. Come to think of it, you're actually probably more "helpful" and generally less salty in PM. 

I like this sort of "help" you provide lol Took about 2minutes and that was only going back through a handful of my own threads and lately. Keep up that helpfulness




So yeah, I guess maybe that's the way "I" wanna be and nothing to do with you at all lol

Ah well, we'll always have Paris xox

[Kinkstaah]

Other than the curvature of the earth, they are kind of all valid points

But yes O2 gauge is kind of needed, everything else seems "fine"

If you wanted to get real creative you could measure your VSS against time, to see if you were really slower between two specific points/runs. This however would require the problem to be reproducable at will. Or at least happen while you are logging it.

Note: I didn't see the boost actually hit the limit of what the ECU is seeing at all. MAP pressure was all 21.5ish points, when it goes over the limit it will just flatline at 22.8 or w/e it is. The graphs do not show this.

[No Crust Racing]

Given the context of those comments, not really

Dyno will fix all with new map sensor and cams, then all of this will be a distant memory (also closed loop boost unless there's something I'm missing about wy you'd want to be open loop?). 

Still doesn't explain why every comment seems to imply the fuel tables are "odd".

 

[Kinkstaah]

They look "odd" because E85 typically needs "30%" (give or take) more fuel than 98. In the real world its actually a little less.

They also need 30%, all over the rev range. It does differ a little under load (otherwise it would be 30 in every cell!) but not from 19 to 43%.

Yours goes from 19% under low load, to 43% under full load.
In addition to that,  your tables imply that you add 133% of the correction when you have 80% ethanol in the tank.

This would mean it would be 133% of 43%.

20% is too little and your E85 would be dangerously lean.
43% is too much and this means either your E85 map is fine (and your 98 is too lean) or your E85 is too rich.

Note: The above numbers are when 100% of the correction is being applied to a decent base map.
However.... yours is 133% of the numbers applied!.

133% of the correction being applied means that everything is 'out' even further'. The numbers are impossible numbers, it can't be correct, unless something is making it be correct, which is what the O2 WB does, it adds and removes fuel to try and hit the target on the "Target AFR" map, which is basically closed loop fuel control. The Target AFR map doesn't appear to be too bad as it's looking for 12:1 AFR under full load.

It is common/advised practice to have the base map as accurate as possible, and not have an O2 controller have a monstous effect, though the Haltech lets it apply up to 25% more or 25% less fuel if need be. If this fails for any reason you are going to have a bad time if it is set up this way.