L83 5.3L Flex fuel conversion with Dyno sheets. Followed with tune and more dyno sheets.

[customboss]

Sadly, unless you are building a engine specifically for ethanol use none of our BTU driven spark engines optimize the mechanical energy capability of ethanol. 

 

CARB sponsored a Cummins spark engine built in Columbus Indiana for E85 use. Performance from a delivery van was amazing.   • Compression Ratio – Optimal range for an E85 optimized engine is 12:1 to 14:1

 

https://www.motortrend.com/how-to/cummins-28l-e85-ethos-project/

 

https://www.energy.ca.gov/sites/default/files/2021-05/CEC-600-2019-022.pdf

 

 

[customboss]

cut out of MPG on differing fuels for a large step van : 

 

 

[M1ck3y]

2 hours ago, customboss said:

Sadly, unless you are building a engine specifically for ethanol use none of our BTU driven spark engines optimize the mechanical energy capability of ethanol. 

 

CARB sponsored a Cummins spark engine built in Columbus Indiana for E85 use. Performance from a delivery van was amazing.   • Compression Ratio – Optimal range for an E85 optimized engine is 12:1 to 14:1

 

https://www.motortrend.com/how-to/cummins-28l-e85-ethos-project/

 

https://www.energy.ca.gov/sites/default/files/2021-05/CEC-600-2019-022.pdf

 

 

 

LT engines are made for use with e85...

 

K2's have the wiring for the sensor, and the necessary tables in the ecu. Just has to be turned on.

 

GM scrapped it because the government was no longer handing out subsidies for it. 

[M1ck3y]

3 hours ago, CamGTP said:

On page one I posted a picture of a 2015 5.3 files high octane timing and the flex fuel spark adder. If we go by that picture the timing allowed is only going to be around 18-20ish and then it uses all of it's adders to get it higher. Like a gas spark adder, IAT, ECT and VVT will all add timing. It's hard to give an exact answer on what the max allowed timing is because it can change from cell to cell in the timing tables. You seeing mid to upper 20's surely does seem possible though.

 

And in the summer I run pump E85 which was usually around 60-70% at the pump, I noticed no huge difference once over 50%. Lots of people do say that once you are over that 50-60% mark that it's not doing a whole lot more power. It would make a difference if you were running E85 or E98 racing fuel.

 

I'm seeing 26 degrees in the summer, 27-28 degrees fall/spring on 94 octane e15.

 

That's why I was curious about how much higher e85 would push it. Or maybe it won't move the timing at all?

 

I do see some knock at wot, but it hasnt really gone much higher then 3. Usually no timing ****** as well. Or at least minimal.

 

  

[M1ck3y]

On 10/27/2021 at 10:18 AM, truckguy82 said:

I’ve never driven a car with e85, they dont offer it in my area.

 

but I would think the e85 changes ignition and fuel timing. I would think that would give you a boost in the low end too. Maybe it only changes the open loop tables? But that doesn’t make that much sense either.

 

hmm

 

What area are you in?

[truckguy82]

21 hours ago, M1ck3y said:

 

What area are you in?

NJ, philly suburbs

[M1ck3y]

If I understand this correctly?

 

Power gained from e85 comes more from the cooling effect and/or increase in air density; rather than a increase in timing from resistance to knock? 

 

 

[TJay74]

On 12/17/2021 at 10:34 AM, M1ck3y said:

 

Thank's TJay74. I don't have hptuners but I do have efilive where I can see where the timing is at any given point. I'm not concerned about what is or isn't changing the timing right now. I know that environmental conditions are what's impacting it for the most part.

 

I guess I should have said..

According to the high octane table what's the maximum allowable advance in timing?

 

I don't know much about tuning, but I have to believe there's more timing to be gained. There's several studies indicating that e40-e50 provides max timing. Anything over e50 and your just benefiting from extra charge cooling not resistance to knock.. 

 

@CamGTP you run e50 don't You?

@lucas287?

E40 -50 doesnt produce max timing, the ECM use a ethanol scaler table in order to determine how much percentage of timing the ECM sees as an adder from the main flex fuel timing table. The scaler starts at 0% then 10% then 20% then 50% then 80% of E85. At 50% (E50) the scaler table is using a modifier of .5 which means if the Flex fuel timing table is offering say 4° of additional timing and the ECM is seeing E40-50 the main timing table is only getting an additional 2° of timing for the E85 fuel. All of those works on a variable sliding scale depending where at on the modifier table the composition is at.

Also not "all fuel in the USA has E10" in it. I live in OKC, we still have 100% gas. It depends on the station and what fuel rack they get their fuel from. I still see E0 at times when I have ran 100%, just like our E85 here is around E80 in the summer months and E60-E70 in the winter months depending on the gas station. We do have a gas station that keeps race fuels on their pumps, their E85 hits dang near at E85 and they sell E100 as well that is spot on.

The problem is N/A just wont see the gains from E85 as say a forced induction engine. My 16 Sierra 6.2 and my 2017 Camaro SS 1LE both saw gains of around 25-30 at the wheels on E60. My 19 Corvette Z06 picked up 70rwhp on E60 over the gas tune. 

My 16 Sierra 6.2 sits around E70-E80 year round, my data logs confirm it sees more timing advance on E75 than it does on E50.

[TJay74]

20 hours ago, M1ck3y said:

If I understand this correctly?

 

Power gained from e85 comes more from the cooling effect and/or increase in air density; rather than a increase in timing from resistance to knock? 

 

 

No the gain also comes from the timing increase, depending on the composition of the E85 you are gaining anywhere from 2°-5° of timing all through the map. 

On my 16 Sieera 6.2 I data logged it from new to now. Even on 91 the gas timing tables are very aggressive and the truck would show knock all times of the year, was much worse during the summer months. Even with 93 in the tank the knock was still present. I spent some time cleaning up the main gas timing tables to try and reduce the knock while on 91/93. 

The moment I put E85 into the tank as soon as the E85 gets over E40 any occurances of knock go away, my truck sits around E70 to E80 year round. I dont ever see knock while I am on E85 whereas if I am on gas even with reduced timing in the main gas timing tables I see tip in knock and burst knock at times even with me reducing the tables some.

[M1ck3y]

@TJay74 you wouldnt happen to know if e85 has higher eg temp would you. Kooks is saying not to use e85 with high flow cats. Which is why I was looking at doing e30-e40.

 

Thanks 

Edited December 22, 2021 by M1ck3y

[Black02Silverado]

2 hours ago, TJay74 said:

E40 -50 doesnt produce max timing, the ECM use a ethanol scaler table in order to determine how much percentage of timing the ECM sees as an adder from the main flex fuel timing table. The scaler starts at 0% then 10% then 20% then 50% then 80% of E85. At 50% (E50) the scaler table is using a modifier of .5 which means if the Flex fuel timing table is offering say 4° of additional timing and the ECM is seeing E40-50 the main timing table is only getting an additional 2° of timing for the E85 fuel. All of those works on a variable sliding scale depending where at on the modifier table the composition is at.

Also not "all fuel in the USA has E10" in it. I live in OKC, we still have 100% gas. It depends on the station and what fuel rack they get their fuel from. I still see E0 at times when I have ran 100%, just like our E85 here is around E80 in the summer months and E60-E70 in the winter months depending on the gas station. We do have a gas station that keeps race fuels on their pumps, their E85 hits dang near at E85 and they sell E100 as well that is spot on.

The problem is N/A just wont see the gains from E85 as say a forced induction engine. My 16 Sierra 6.2 and my 2017 Camaro SS 1LE both saw gains of around 25-30 at the wheels on E60. My 19 Corvette Z06 picked up 70rwhp on E60 over the gas tune. 

My 16 Sierra 6.2 sits around E70-E80 year round, my data logs confirm it sees more timing advance on E75 than it does on E50.

Makes me mad that GM stopped setting up for FF on the new 2019 and up trucks.  You would think they would continue like they did on our 2016 Suburban.  It wasn't FF but the connector was there, just needed to hook up a sensor and open up the tables.  I would rather run E85 than regular gas.  I do mix it but only at a 40/60 mix at the most on my 2019 with the 6.2.

[KARNUT]

37 minutes ago, Black02Silverado said:

Makes me mad that GM stopped setting up for FF on the new 2019 and up trucks.  You would think they would continue like they did on our 2016 Suburban.  It wasn't FF but the connector was there, just needed to hook up a sensor and open up the tables.  I would rather run E85 than regular gas.  I do mix it but only at a 40/60 mix at the most on my 2019 with the 6.2.

One of the things I did like about my 14 GMC. My local grocery store had E-85 1$ cheaper than reg gas. You did feel the difference. On trips I used reg gas. I guess getting with in 25 HP of the 6.2 on E-85 didn’t go down well. Especially since some of the 6.2s power came from premium fuel and tuning for it. 

[M1ck3y]

On 12/20/2021 at 10:59 AM, KARNUT said:

One of the things I did like about my 14 GMC. My local grocery store had E-85 1$ cheaper than reg gas. You did feel the difference. On trips I used reg gas. I guess getting with in 25 HP of the 6.2 on E-85 didn’t go down well. Especially since some of the 6.2s power came from premium fuel and tuning for it. 

 

The 6.2's come with the wiring harness and tuning as well: 6.2's are 100% e85 capable. Gmt900 6.2's are e85 capable from the factory. 

 

E85 support was cut because GM stopped getting paid by the government to include it. Imo, gm didn't include it on the 2014 6.2 k2's because it would be pushing power levels higher then they were comfortable with. That, and the l86 would be advertised as making more horsepower and torque then the LT1. Car owners would be up in arms over that.

[M1ck3y]

On 12/20/2021 at 7:47 AM, M1ck3y said:

@TJay74 you wouldnt happen to know if e85 has higher eg temp would you. Kooks is saying not to use e85 with high flow cats. Which is why I was looking at doing e30-e40.

 

Thanks 

 

In case anyone uses this thread for future reference. E85 doesn't increase egt. The concern is about how ethanol reacts with additives in engine oil. More specifically, a chemical reaction takes place inside the catalytic converter; this reaction is whats damaging, and over time reduces the efficiency of the catalyst. For oem cat's this isn't an issue, they're quite durable. Kooks cats on the other hand have a metallic substrate with a coating of precious metals. I can only speculate that they've determined because of the design, they are at greater risk of failing over and above oe style ceramic substrates.   

[pokismoki]

On 12/20/2021 at 6:41 AM, TJay74 said:

On my 16 Sieera 6.2 I data logged it from new to now. Even on 91 the gas timing tables are very aggressive and the truck would show knock all times of the year, was much worse during the summer months. Even with 93 in the tank the knock was still present. I spent some time cleaning up the main gas timing tables to try and reduce the knock while on 91/93. 

The moment I put E85 into the tank as soon as the E85 gets over E40 any occurances of knock go away, my truck sits around E70 to E80 year round. I dont ever see knock while I am on E85 whereas if I am on gas even with reduced timing in the main gas timing tables I see tip in knock and burst knock at times even with me reducing the tables some.

just curious but are you running factory thermostat and stock fan settings while experiencing this knock?

Edited January 21, 2022 by pokismoki