LNF Ethanol experiment

[Iam Broke]

Glad to keep it interesting, T.

Here's mine... just a bit more aggressive than Andy's up top.

[Jaxon]

Andy looks to have showed the comparison from stock to what hes running. You sure are running some timing tho lmao.


Edit: Holy shit, gimp, how are you running so much timing? using those for comparison to the stock table is CRAZY compared to what I've been running. Alot more timing than IAB is running for the most part as well. I can't believe your running so much timing. I am stumped. What are your DALs? I know that my car just spikes in the 240s and drops down to ~170 by 6300.

[T-Man]

Glad to keep it interesting, T.

Here's mine... just a bit more aggressive than Andy's up top.

Much appreciated too!

My good god... You and Gimp are running an ASS LOAD of timing...

Heading to fill up now!!!

[Gimpster]

Oh hell with it, here is my current timing map attached. I hope nobody tries to run his or my timing out of the box. Please ease into it.

Tom, it looks like I might've gone a bit more aggressive since we last swapped tunes. I just emailed you the latest/last tune I ran at the track. I kept feeding it a little more and more timing at the track up top and it kept getting faster. Either way it doesnt matter, your car flows so much better due to mods + stage1 base code... you're in the sweet spot a hell of a lot more than me. I end up a column back after 5500RPM.

Jaxon both of our cars are just taking it, really no knock to speak of except for the occasional phantom knock as IAB reported (nice acronym btw heh). The corn nectar is sweet indeed...

Whats key here to me is how flipping HOT its been in the midwest lately and still no knock. I can only imagine what IAB's 60-100's are going to be like when he catches a dry 60F morning. He's well into the 4's easy with the right conditions. The best I've mustered on an 82F morning has been 5.677.

My DAL's net me the same loads as you. Basically spikes 240 and then trails to the lower 170's by redline. I'm still running the stock map sensors so I don't have the sweet WG control Iam Broke does. Nor do I have an intake, dp... blablabla so obviously his car would cream mine and his load shows it! I own those mods but am reluctant to put them on. I don't have a place to do a clutch right now, and I know I'll just destroy the stocker if I make the car flow. MAF typically flows high 31/low 32 through the pulls.

In the end we're just reporting what most people do after playing with e85 I guess.

[Jaxon]

Lol gimp, sounds the same as me. I am going to be getting a better tune here soon and pushing the boost a little higher. I might even dish out for the trifecta+hpt stuff since my local tuner is now doing that. I had another person tuning it but after not getting a response for a month I've given up. I'm trying to save up a little cash here and there for mods and tuning but its not very easy with me and my wife both being unemployed currently... Midwest has been crazy lately. It was 100+* ambient today. I'm thinking of putting a little more e85 into it. I might make one of those ethonol testers myself instead of spending the $20+ on it.

A local guy is getting some pretty good results from the stock turbo, over 300whp for sure and is smoking some fast cars from rolls. Full bolt ons + stage and tuning. He is not new to the cobalt game either, his s/c put down over 400 at the wheels on a small shot and stock but ported blower.

[Iam Broke]

I'm doing a compression test today to see how bad I've creamed the rings.
No issues, just checkin'.

I don't think I can run as much mid rpm high load timing as Andy since I see 280% airloads even in the heat. I was starting to see a bit of KR on 2 & 4 but not enough to retard the timing so I cut back .75* in those areas. Trying to see if 29% E helped or hurt but it got so damn hot I can't tell yet. It's a pinch slower, but prob heat related.
On E35 I had a 5.2 sec 60-100 with 95* ambient, 75% humidity & 115* IAT2's.

Edit: Compression test good for 42k miles.

#1 - 160
#2 - 160
#3 - 152
#4 - 155

I've been concerned about it since running a TF tune for a few months before I got HPT and a lot of help from T2 & others.

[T-Man]

Alright, I can officially say that the Banana Sedan loves the corn

I have 6 gallons of 91 and 1.5 gallons of E85, so nothing too crazy. I was able to bump the timing up quite a bit over what I was barely able to run with just 91 octane. I also noticed that any and all mid-range KR, real or not, is gone. Only got a little bit of knock on one run but was due to whacky fuel trims (+4%) but quickly went away and pulled strongly to redline.

Average STFT is around -2 to .08 and LTFT sits at -.08 and this is with the MAF correction table with all 1's / Stock MAF Freq. Little trimming should help clear up the misc. whacky trims in a few areas.

PE Lambda at .88

Overall, I'm fuckin hooked!

Thanks IAB and Gimp

Edit - Forgot to mention that IAT's were at or over 100 at all times. Gotta love the desert...

[Iam Broke]

[2000Firehawk]

I've been running a true E35 for almost a year now with lots of timing, & loving it.

Some math to figure out the exact ratios of your mix.
A true E25 mix = one gallon of E85 + four gallons of E10.
A true E35 mix = one gallon of E85 + two gallons of E10.
85 + 10 + 10 divided by 3 = 35
85 + 10 + 10 + 10 +10 divided by 5 = 25

E35 = 5 gallons of E85 + 10 gallons of E10 on a fillup for me...

E0 = 14.64 AFR = stoich of 1.0 with WOT = .88
E10 = 14.076 AFR = stoich of .96 with WOT = .85
E25 = 13.231 AFR = stoich of .90 with WOT = .80
E35 = 12.668 AFR = stoich of .87 with WOT = .77

The LNF loves ethanol...
Just running a little ethanol, E10, works wonders.

E10, + 5 degrees more timing everywhere, makes for a very happy LNF.

E35 + 10 degrees everywhere makes the LNF a monster...:cheers

I don't want to try anymore than a E35 mix, as it may be pushing the limits of the LNF fuel system.

I just read an article that states that the knock supressing ability of ethanol is reached when you hit E20, so, I'm going to switch to E25 to see how it compares to my E35 setup. If I can tune E25 to the same power levels of E35, then I'll stay with E25. The main reason that I would like to stay with E25 is, if I can't find an E85 pump to blend, when on a trip, E10 will be ok to use without worrying about reprogramming to ECM.

[Iam Broke]

Why are you richening up PE lambda? The wideband 02 adjusts accordingly. You are running too rich IMO. I'm running .90 PE lambda at 40% E and making a buttload of power with no knock. Wideband 02 says fuel trims are right on at WOT and LTFT's are dialed in accordingly for cruise. 7% MAF freq shift from E10 to E40 on the LNF and still in the injection window at 5.2 ms@6k rpm, our limit at 6k is 5.6 ms. Might hit 5.6 ms when it gets colder out, time will tell.

The 7% shift in the MAF freq doesn't necessarily equate to a 7% fuel shift as the MAF freq is not linear, closer to the square root curve as flow sensing primary elements typically are.

The 02 sensor doesn't care if the excess 02 comes from gas or ethanol, all it knows is 02 content. The injectors squirt more to make up the differences. That's what's great about having a factory 02 wideband and also what causes the LTFT drift when you increase E to the positive side, it's adding fuel.

Lambda is 1.0 at Stoich, regardless of fuel.

[quickboat]

I'm running some Sea Foam to clean the injectors n such but after this tank I will start playing with the E85. I'm getting 25psi thoughout the rpm range a little insurance wont be bad. Its a shame they used cast pistons in these motors. They fit tighter but Hyperetics would have been much more durable and fit tighter then forged!
Hyperectic FTW!

[Iam Broke]

At least they have the oil squirters on the skirts.

[Terminator2]

I'm running some Sea Foam to clean the injectors n such but after this tank I will start playing with the E85. I'm getting 25psi thoughout the rpm range a little insurance wont be bad. Its a shame they used cast pistons in these motors. They fit tighter but Hyperetics would have been much more durable and fit tighter then forged!
Hyperectic FTW!

The stock pistons in the LNF are hypereutectic.

[Iam Broke]

Not sure, here's a xls I have on the LNF...it says cast.

[quickboat]

Term, wher did you read that? The build book just says cast and also says they are only good to 300hp.
Broke the squirters do help cool them but forged take detonation much better.
My brother has a scion TC that he turboed and his forged pistons are quite loud. They are on the top of the clearance limit but it sounds wild.

[Terminator2]

I've been running a true E35 for almost a year now with lots of timing, & loving it.

Some math to figure out the exact ratios of your mix.
A true E25 mix = one gallon of E85 + four gallons of E10.
A true E35 mix = one gallon of E85 + two gallons of E10.
85 + 10 + 10 divided by 3 = 35
85 + 10 + 10 + 10 +10 divided by 5 = 25

E35 = 5 gallons of E85 + 10 gallons of E10 on a fillup for me...

E0 = 14.64 AFR = stoich of 1.0 with WOT = .88
E10 = 14.076 AFR = stoich of .96 with WOT = .85
E25 = 13.231 AFR = stoich of .90 with WOT = .80
E35 = 12.668 AFR = stoich of .87 with WOT = .77

The LNF loves ethanol...
Just running a little ethanol, E10, works wonders.

E10, + 5 degrees more timing everywhere, makes for a very happy LNF.

E35 + 10 degrees everywhere makes the LNF a monster...:cheers

I don't want to try anymore than a E35 mix, as it may be pushing the limits of the LNF fuel system.

I just read an article that states that the knock supressing ability of ethanol is reached when you hit E20, so, I'm going to switch to E25 to see how it compares to my E35 setup. If I can tune E25 to the same power levels of E35, then I'll stay with E25. The main reason that I would like to stay with E25 is, if I can't find an E85 pump to blend, when on a trip, E10 will be ok to use without worrying about reprogramming to ECM.

The LNF PCM is programmed in lambda not A/F so 1.00 lambda is 1.00 lambda regardless of fuel. The WB will sense the differening O2 content of the ethanolated gasoline and lengthen IPW accordingly. A little MAF tuning will keep the LTFT and STFTs in check. We have no access to programmed stoich values for this ECM currently (If it even posesses them) so we have no other way to do it. There is no sense running it that rich it wil just loose power no matter how much timing you throw at at.

[quickboat]

Term, thanks for the spelling correction. I shredded that one lol
hypereutectic FTW!!!!!

[Iam Broke]

I do see the error in my % volume calcs now Firehawk, thanks!

Should be as follows I think...

6:1 is 20%E
5:1 is 22.5%E
4:1 is 25%E
3:1 is 29%E
2:1 is 35%E
1:1 is 47.5%E

So from this I'm currently at 29% with a 7% MAF freq shift. Next week I'll increase it to 35% then or 2 gals E10 to 1 gal of E85

When I'm down to 10 gals in the tank tomorrow night, I'll add another gal of E85, that will put me very close to 35%.

[Iam Broke]

As usual, Term is probably right! Hypereutectic pistons can be forged or cast. From Wikipedia...

Forged versus cast

When a piston is cast, the alloy is heated until liquid, then poured into a mould to create the basic shape. After the alloy cools and solidifies it is removed from the mould and the rough casting is machined to its final shape. For applications which require stronger pistons, a forging process is used.
In the forging process, the rough casting is placed in a die set while it is still hot and semi-solid. A hydraulic press is used to place the rough slug under tremendous pressure. This removes any possible porosity, and also pushes the alloy grains together tighter than can be achieved by simple casting alone. The end result is a much stronger material.
Hypereutectic pistons can be forged, but typically are only cast, because the extra expense of forging is not justified when cast pistons are considered strong enough for stock applications.

Ours may be cast Hypereutectic.

[quickboat]

Broke, I would hope so since it is a much better piece. Forged is the way to go on a rebuild, but you want to be real good on the clearance calculations.