E85 Conversion

[Hog]

Just to see what GM is doing with their new engines on the Flex-Fuel front.
I do see that the newer K2XX trucks from 2014+ are running the new GEN-V SBC with direct injected Ecotec-3 engines, some are flexfuel like the L83 5.3 and the LV3 4.3 liter V6. I included the L86 6.2, even though it isn't a Flexfuel engine just to show how well these newer Durect Injected engines do.
L83-5.3 355hp @ 5600rpm/383 lb·ft @ 4100rpm on gas
376hp @ 5600rpm/416 lb·ft @ 4000rpm on E85
21hp/33 lb/ft torque gains in SAE ratings using E85 the L83 5.3 uses an 11:1 compression ratio

L86-6.2 420hp @ 5600rpm/460lb·ft @ 4100rpm
The L86 6.2 liter/376cid runs a 11.5:1 compression ratio, this is the truck version of the C-7 Stingray's engine. They are both GEN-5 SBC's.


Even the LV3 V6 does better on E85. This V6 has an 11.0:1 c/r.
285hp @ 5300rpm/305lb·ft @ 3900 rpm
297hp @ 5300rpm/ 330 lb·ft @ 3900 rpm on E85Gains of 12hp @5300rpm/25 lb/ft torque @3900rpm on E85.

With these truck engines, I'd bet that there is some ECM tuning funny business at play here. GM supplies vehicles with Flexfuel engines to make the Gov happy, and then tunes them slightly more aggressive when E85 is in the tank so that folks will buy them and then choose to burn E85. This keeps the farmers happy to supply the ethanol plants. The Gov. then backs off on corn subsidies.


As to Todds response, agreed in a true N/A E85 to gas compare with ECM tuning optimized for BOTH gas and E85, the E85 should show less power. To see a power advantage while running E85 in a N/A setup would require an increase in compression. In doing so, your engine would from that point forward be a race gasoline or alcohol/E85 only engine due to the increase in compression.

[LGAFF]

So if you search the net a lot of NA Cars making significant increases in power 20 to 30hp. Illinois also has a significant # of stations with E85



http://www.superchevy.com/how-to/vem...85-conversion/

Alot of LS engines conversions with similar results and NA.....

[Kevin]

make sure you change out the fuel lines too

[LGAFF]

Even a stock Coyote with an air intake and exhaust as the only mod made about 12-14rwhp on just switching to E85

[LGAFF]

https://www.youtube.com/watch?v=cT_3JLg7KeA

[LGAFF]

I will put E85 Conversion on my list for late 2017

[XfireZ51]

So if u run a straight E85, then the changes to the calibration are fairly straight
forward. You will need to confirm that u have the fuel delivery necessary since u r going from 14.7 to 9.0:1 AFR for stoich. That's about 30-40% more fuel.
The change involves the injector constant, stoichiometric air/fuel ratio, and tweaking of the VE tables and timing. BOTH the injector constant and command stoichiometirc air/fuel ratio constants affect the pulsewidth substantially. You'll need to confirm that the existing fuel system will accomodate the increase in fuel flow required. By adjusting the stoichiometric air/fuel ratio you are adding the proportional amount of pulsewidth automatically. Same goes for the injector constant, when you increase the value the pulsewidth decreases. Both are global changes in fuel delivery, which means small tweaks to the VE tables.
It would be nice to have code incorporated as part of our calibration to utilize Flex Fuel sensor data to affect the stoich etc so as to automatically accomodate
variation in the ethanol content. Otherwise it becaomes a matter of
switching bins for the appropriate ethanol content.

[LGAFF]

Dominic it seems to me the Z already has the pump/inj capacity to run both....could you not just swap proms if need be to move back and forth between fuels?

[BigJohn]

Do you need stainless fuel lines?

[LGAFF]

Classic tube has them, about $250 for everything....swap out all orings