Dual maps for E-85 and gas? - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

granatl · 12-18-2012, 03:21 PM

About 1/2 a year ago, I was told that the tuning parameters for E-85 can be loaded into the high octane maps, and then a set of lower timing (& different fueling) can be placed into the low octane maps. Then, there's some way to connect to a pin on the PCM and then have a toggle switch to flip between the two.

Does anyone have the instructions to do this that they'd care to share?

SinisterEcho · 12-18-2012, 03:44 PM

I would be intrested in this as well!

Iam Broke · 12-18-2012, 03:56 PM

More has to be changed than the timing tables. E85 requires ~30% more fuel than gasoline.

I do not know of a pin on our ECU that can be grounded to shift dual tunes. Perhaps Trifecta or another aftermarket programmer has a custom OS that can.
I know TF ran dual tunes on the Bosch E69 ECU on the 4 cyl LNF Turbos for different boost levels selectable by the CC button or TC button.

The stock fuel system isn't going to keep up well on E85, I see fuel rail pressure drop from 58 psi to 52 psi on a tuned LS3 on E47. (~15% more fuel @ .87 PE Lambda) & IDC at 80% already. E85 will cause the pressure at the injectors to drop further and Inj duty cycle will rise even more. Most tuners advise not to have IDC run over ~80%.

E47 is a blend of E10 93 & E85 1:1 and is ~99 octane. Not much trouble to blend 1:1 at the pump. If you want to run E85, the injectors may be large enough (it'd be close stock engine to 95 % IDC IMO) but you will prob need a ZL1 in tank fuel pump.

granatl · 12-18-2012, 04:02 PM

I think my Google search finally yielded results...

http://forum.efilive.com/showthread....ight=flex+fuel

Iam Broke · 12-18-2012, 04:13 PM

Let us know how it works out.

granatl · 12-18-2012, 04:44 PM

I should probably mention that I'm about to install 85# injectors and already have dual fuel pumps. Fuel delivery won't be a problem for me.
keeping the tires glued to the pavement, well, that's a whole different problem!

SRT10KLLR · 12-19-2012, 07:20 AM

It doesn't use the high and low octane tables but rather has separate E85 fuel and timing tables.

I was going to use the EFIL COS to run the nitrous. I added the pin to the ECM and just needed to ground the wire when I activated the nitrous but I never finished wiring it. Went twins instead and now that the car has the HPT 2.5 bar tune EFIL can't read it.

Here is the other thread.
http://forum.efilive.com/showthread....-release/page8

redredrage · 12-21-2012, 07:43 PM

okay, so its been 20000 miles and I've been putting in 5 to 6 gallons of e85 with 10 to 11 gallons of 89 gas (its cheaper than 87..... 87 is lawn mower gas)

results are better performance, reduced high way economy (this is good) no difference in city economy

overall your money up and your egr, intake tb as well as injectors should be cleaner....

oh and also when i can't find e85 on long trip, i just use premium

no modification needed ...... go gasahol

12-18-2012, 03:21 PM	#1
granatl Drives: 2SS RS ABM A6 Join Date: Jun 2010 Location: Pahrump, NV Posts: 273	Dual maps for E-85 and gas? About 1/2 a year ago, I was told that the tuning parameters for E-85 can be loaded into the high octane maps, and then a set of lower timing (& different fueling) can be placed into the low octane maps. Then, there's some way to connect to a pin on the PCM and then have a toggle switch to flip between the two. Does anyone have the instructions to do this that they'd care to share? __________________ Jack Bilger

12-18-2012, 03:44 PM	#2
SinisterEcho Drives: 2010 2SS/RS M6/LS3 Join Date: Oct 2011 Location: Arvada, Co Posts: 9,872 View My Garage	I would be intrested in this as well! __________________ My Mod Journal <-- Its updated... again!

12-18-2012, 03:56 PM	#3
Iam Broke PHAT B33 Drives: 2012 TF3 Camaro 2SS/RS M6 Join Date: Jun 2012 Location: Dark of the Moon Posts: 1,460 View My Garage	More has to be changed than the timing tables. E85 requires ~30% more fuel than gasoline. I do not know of a pin on our ECU that can be grounded to shift dual tunes. Perhaps Trifecta or another aftermarket programmer has a custom OS that can. I know TF ran dual tunes on the Bosch E69 ECU on the 4 cyl LNF Turbos for different boost levels selectable by the CC button or TC button. The stock fuel system isn't going to keep up well on E85, I see fuel rail pressure drop from 58 psi to 52 psi on a tuned LS3 on E47. (~15% more fuel @ .87 PE Lambda) & IDC at 80% already. E85 will cause the pressure at the injectors to drop further and Inj duty cycle will rise even more. Most tuners advise not to have IDC run over ~80%. E47 is a blend of E10 93 & E85 1:1 and is ~99 octane. Not much trouble to blend 1:1 at the pump. If you want to run E85, the injectors may be large enough (it'd be close stock engine to 95 % IDC IMO) but you will prob need a ZL1 in tank fuel pump. __________________ Another 1 of 371 '12 T3 LS3 M6's built.

12-18-2012, 04:02 PM	#4
granatl Drives: 2SS RS ABM A6 Join Date: Jun 2010 Location: Pahrump, NV Posts: 273	I think my Google search finally yielded results... http://forum.efilive.com/showthread....ight=flex+fuel __________________ Jack Bilger

12-18-2012, 04:13 PM	#5
Iam Broke PHAT B33 Drives: 2012 TF3 Camaro 2SS/RS M6 Join Date: Jun 2012 Location: Dark of the Moon Posts: 1,460 View My Garage	Let us know how it works out. __________________ Another 1 of 371 '12 T3 LS3 M6's built.

12-18-2012, 04:44 PM	#6
granatl Drives: 2SS RS ABM A6 Join Date: Jun 2010 Location: Pahrump, NV Posts: 273	I should probably mention that I'm about to install 85# injectors and already have dual fuel pumps. Fuel delivery won't be a problem for me. keeping the tires glued to the pavement, well, that's a whole different problem! __________________ Jack Bilger

12-19-2012, 07:20 AM	#7
SRT10KLLR Drives: 2010 Camaro 2SS/RS Join Date: Sep 2009 Location: Down South Posts: 1,497	It doesn't use the high and low octane tables but rather has separate E85 fuel and timing tables. I was going to use the EFIL COS to run the nitrous. I added the pin to the ECM and just needed to ground the wire when I activated the nitrous but I never finished wiring it. Went twins instead and now that the car has the HPT 2.5 bar tune EFIL can't read it. Here is the other thread. http://forum.efilive.com/showthread....-release/page8 __________________ 2005 Dodge Ram 2500 RCSB Thunder Road Hemi Sport w/STS Turbo 2004 Dodge Ram SRT-10 - Silver - Stock 2003 Chevy 1500 RCSB Stepside 400SS - 408 in now awaiting Turbo

12-21-2012, 07:43 PM	#8
redredrage Drives: 2010 Camaro SS manual all stock Join Date: Jun 2012 Location: Royal Oak, MI Posts: 160	okay, so its been 20000 miles and I've been putting in 5 to 6 gallons of e85 with 10 to 11 gallons of 89 gas (its cheaper than 87..... 87 is lawn mower gas) results are better performance, reduced high way economy (this is good) no difference in city economy overall your money up and your egr, intake tb as well as injectors should be cleaner.... oh and also when i can't find e85 on long trip, i just use premium no modification needed ...... go gasahol