if i tune on real e85 will ecu adjust for e70?

[twistedneck]

2012 boss heads and cams. 47lb injectors makes about 450 whp on 93.

Stock fuel pump.

Going to e85 for a touch more power, better smell w the o/r x, and cooler temps in the stock pistons.

I'm going to tune with e85 in summer so its real 85. Question is when the spring and fall come around and e85 becomes e70 will my long and short term trims be able to adjust the Afr to keep the motor from getting too rich? Will I lose a lot of power in that mode?

Thank you

 

[bambinov8]

No it will not adjust. Get the e85 tester and Don't go WOT if you get e70 since 22*-23* will not forgive

 

[twistedneck]

No it will not adjust. Get the e85 tester and Don't go WOT if you get e70 since 22*-23* will not forgive

Got it, i think i'm more like 26 advance on 93 gasoline based on my logs.

so when i see E70 with the tester its time to either end the season or change back to gasoline.

I can get the tester and distilled water, but is there a simple way to USE that little tester before / after filling up? do you have a 1gal gas can with you at all times or just a small funnel?

 

[Sof Top]

Or get a tune for e70 and switch tunes if needed.

 

[bambinov8]

So

 

[Mystic03]

lower ethanol richer it will be wouldnt it?

 

[Radar Doc]

lower ethanol richer it will be wouldnt it?

Yes, will be slightly rich. Only ill effect is a bit more popping out the exhaust on decel.

 

[twistedneck]

Yes, will be slightly rich. Only ill effect is a bit more popping out the exhaust on decel.

What about detonation from timing set for e85?

Tuners want one fuel to tune to it seems the ecu can't adjust properly

 

[Radar Doc]

What about detonation from timing set for e85?

Tuners want one fuel to tune to it seems the ecu can't adjust properly

Of course, it's always best to ask your tuner these questions and I always recommend data-logging to confirm your own setup, but here's my experience...

I started running E85 almost two years ago with a Lund tune. Data-logged that tune on E85 and E70 and had no signs of knock. His timing values don't exceed MBT, and I doubt other tuners do either. The only issue I noted was the exhaust popping on decel. Otherwise, the car ran just as good on E70 as it did on E85.

In July of last year, I started tuning a bit myself using the SCT Pro Racer software. This allows me to change the stoich value in my own tunes for E70 during the winter months, which significantly reduces the decel exhaust popping. I'm not running beyond MBT on either blend.

I only switch to gas when I'm heading to southern states where there are almost no E85 stations.

 

[Mystic03]

What about detonation from timing set for e85?

Tuners want one fuel to tune to it seems the ecu can't adjust properly

detonation for e85 would be rare. imo as long as its 85% or lower it wont detonate...just my take on it im sure 04sleeper will chime in soon!

 

[65fastback2+2]

going from summer to winter e85 just makes your tune slightly rich.

you're talking about 1/2 a point or less in AFR typically which is fine.

secondly, your pcm is going to try and add/remove fuel to achieve commanded AFR...if it wasnt, then you could remove all 02 sensors, but everyone knows you cant do that.

thirdly, over 60% ethanol, the returns on the benefits are vastly diminishing...and you wont see less than e70 out of a pump anyhow.

so, if it was my vehicle, I tune it on summer e85, then forget it and drive the mess outta the thing year round.

my 500 rwhp lightning was tuned on winter e85, and I just let it go slightly lean. beat on it year around as well.

 

[Shaun@AED]

Yes, the tune will adjust in the 2011+ Copperhead ECU's. Not like a Flex Fuel vehicle, but you will not run rich / lean as these cars are Closed loop wideband controlled vehicles.

Running lower Ethanol content will result in a rich condition that the ECU will pick up and lean out via fuel trims. Idle, Part throttle, and WOT.

 

[vladSVT]

Yes, the tune will adjust in the 2011+ Copperhead ECU's. Not like a Flex Fuel vehicle, but you will not run rich / lean as these cars are Closed loop wideband controlled vehicles.

Running lower Ethanol content will result in a rich condition that the ECU will pick up and lean out via fuel trims. Idle, Part throttle, and WOT.

Since we're on the same topic sort of, will a Terminator ecu adjust the air fuel with car that has no O2 sensors?
I was thinking about putting a slightly smaller pulley on (3.5 now and want to put 3.25) so its only going to pick up around 1.5-2psi at that, will the MAF compensate or will I have to adjust the tune? Some told me that this much boost shouldn't matter, and the MAF should adjust it accordingly. (I have SCT Big Air)

 

[Shaun@AED]

Terminators are closed loop at idle and part throttle only, and they do not have wide band O2's.
Any fueling adjustments for stoich changes are still accounted for via fuel trims, but only at idle and part throttle.

Changes for airflow (smaller pulley) are a totally different part of the tune strategy and the Maf does compensate, but its best to get the car on the Dyno with a quality wide band installed to be sure everything is good.

 

[twistedneck]

So the tune won't know its rich because the stoich value will be set for e85? Then all it can do is pull timing? Or is it going to see less oxygen at the O2 sensor because the mix is now rich w e70, and its going to pull fuel w trims until that balances out?

I see the stoich setting as the coarse adjustment and the trims as the fine adjustment.

Correct where I'm wrong please.

 

[c6zhombre]

No it will not adjust. Get the e85 tester and Don't go WOT if you get e70 since 22*-23* will not forgive

Did you ever actually test e70 in Florida? It's been basically e85 or better here in Texas all year long, several city locations that I've noticed (south tex/Corpus, DFW, and Houston).

 

[Radar Doc]

Yes, the tune will adjust in the 2011+ Copperhead ECU's. Not like a Flex Fuel vehicle, but you will not run rich / lean as these cars are Closed loop wideband controlled vehicles.

Running lower Ethanol content will result in a rich condition that the ECU will pick up and lean out via fuel trims. Idle, Part throttle, and WOT.

Shaun,

I've always understood the STFTs and LTFTs (or whatever adaptive measures) to adjust the mixture so that measured AFR equals the commanded.

So, if my stoich is set to 9.85 for E85 and WOT lambda is, say 0.84 at a given RPM, then the computer (based on O2 sensor input) is going to use STFTs and LTFTs (or whatever adaptive measures) to make that so (9.85 x 0.84=8.274 AFR).

If I'm running E70 with these parameters, I believe the car will run somewhat rich because the computer will be commanding 8.274 AFR (and measured will be 8.274) when the AFR should be 10.6975(E70 stoich) x 0.84=8.9895. Not a huge difference, but still rich.

I know you're busy, but if you get a chance and can explain why my thinking is wrong, I'd certainly appreciate it.

Thanks,
Mike

 

[Shaun@AED]

It's easier to think in Lambda rather than Air Fuel. Air fuel is stoich multipled by Lambda, but it's a lot easier to do all calculations with Lambda first and not worry about actual Air Fuel as most wide band software is setup for zero ethanol gasoline, which makes the conversions difficult.

I have an ECM 1600 Lambda meter which simplifies things. .84 commanded, .84 on the Lambda meter. Adjust Maf curve based on the fuel trims.

What I do (similar to Ford Flex fuel strategy) is dial in the Maf curve on a known Ethanol content gasoline. Once the tune & Maf curve is dialed we swap to E85 and monitor fuel trims. Based on the trims I adjust the Stoich till fuel trims match the Gasoline logs. This gets the E85 tune very close to the actual Ethanol content.

Shaun,

I've always understood the STFTs and LTFTs (or whatever adaptive measures) to adjust the mixture so that measured AFR equals the commanded.

So, if my stoich is set to 9.85 for E85 and WOT lambda is, say 0.84 at a given RPM, then the computer (based on O2 sensor input) is going to use STFTs and LTFTs (or whatever adaptive measures) to make that so (9.85 x 0.84=8.274 AFR).

If I'm running E70 with these parameters, I believe the car will run somewhat rich because the computer will be commanding 8.274 AFR (and measured will be 8.274) when the AFR should be 10.6975(E70 stoich) x 0.84=8.9895. Not a huge difference, but still rich.

I know you're busy, but if you get a chance and can explain why my thinking is wrong, I'd certainly appreciate it.

Thanks,
Mike

 

[twistedneck]

Without a bap, using 47lb injectors will my fuel system handle e85?

I sized it this way because a non supercharged engine the injector and fuel pump requirements are a lot lower.

Edit: kdanner went 180 at the Texas mile with same heads and a cobra jet intake on e85.. That means my injector duty cycle should be ok...

Next step up is id1000 and a kb bap. But that is for later when I have high compression and 8200 rpm, huge Tb, cj intake, etc.

 

[twistedneck]

I think Michigan stays like this until July, I will continue testing it. My plan is to get a tune for this E75 and then just purchase another tune for E85 when that is available. According to the E85 website it only stays 85 in Michigan for one month.

If you notice that its not filled up all the way, that's because it actually loses volume when you shake it up and mix the solution. it was right to the top line when I added the water to the fuel.

Worst case, I test every tank and watch it change, and if it goes to E80 then i'm running lean and need a tune for that. When it hits E85, same thing. ugly, but it will keep it running right. Thoughts? Freakin stank (stunk) super bad today in the drive thru - 93 fumes w/o cats burns your nose and throat.