After installing the sensor and enabling it via HPT does it just work without further tuning? I do realize that more power could be had with proper tuning.

I need to look and see if EFILive has the FlexFuel parameters available.

 

Requires tuning. The flex fuel stuff isn't filled in, or at least on a c6 it isn't. You have to go fill in the values and tell it what to do.

 

It's filled in on the c7, but the stoichtable needs to reflect flex fuel n a few other things. I'll take pics later n post

 

Thats good to know. I wanted to try E85 now while the car is stock, then eventually go FI.

 

Cool. I need to decide how much I care about my C7 warranty...

I wish that Flex Fuel was baked in to the OS used on my 2002 C5. I'd like to convert it as well.

 

7liter it can work, just have to swap operating systems

 

All good news, I will be finishing the install tomorrow after work, and should have a fresh tune come next week as well. Everything I find I plan on sharing

 

Awesome ls3, get me some pics of your ground n power (hate wiring). I'll post up later too when I have more time

 

How did u go about getting the sensor and plug and braid line ect.. like u get a c6 sensor or what?

 

No kidding? I did not know that.

So I can add the appropriate sensor, wire it in to some pin on the ECM, and have a LS1B controller automatically adjust for varying amounts of ethanol content?

Do you have any links with info on what I'd need to do?

 

Simple, I believe Pace Performance is vendor so Ill post some links


Flex Fuel sensor part number 13577429(my favorite, OEM, cheaper and more compact)
http://paceperformance.com/i-1080149...ensor-e85.html
Connector part number 13352241 (cut the end off and use the 3 existing wires) sensor pigtail has a black (ground), pink (Power), and a white (ECM). ECM C7 Pin is X1 Pin 38
http://paceperformance.com/i-8396465...r-harness.html

Use the factory Fuel line to connect to the entry end of the Flex fuel sensor and use a 3/8 quick disconnect to connect to the other end of the sensor and then connect to factory fuel supply entering the rail. I bought a C5 factory braided hose that is long enough and has the perfect ends, entire install will look OEM and be somewhat hidden.
Ill have everything Saturday and I will get pics up this weekend.


Here are the most important tables In the calibration dealing with E85
I can explain the tables if anyone wants additional input





Also go into DTC's and enable P0178 and P0179 which deals with the High/Low Circuit for the Flex fuel sensor(Pic is Above)
Also, as many of you can see the Spark tables are there and just needs the Stoich table modified like above. The C7 Z06 however all tables are Zeroed out dealing with alcohol. Some have reported in the tuning world enabling Alcohol ONLY with no changes of the Spark tables and gain 4MPH and 40hp. Basically for around $150 you can have C6 Z06 power, best bang for the buck mod I know of.

 

I know of an LT1 on motor that made around 585rwhp on E85 with factory injectors and mechanical pump, rail pressure was increased to around 2500psi for a little cushion but he had a cam lobe for increased fuel but there was room left still.
Maybe the owner will chime in, he's the only one with a 427 I know of!!!

Most of the when pumping E85 in the tank still only comes out to around E70 since its usually diluted with regular gasoline which in todays world has up to 10% ethanol anyways. That's why the factory C7 uses a stoich of 14.10 instead of the traditional 14.68 (there is no more Gasoline at 14.68, haven't seen that in years)

Id say with increased rail pressure and with addition of the mechanical Z06 fuel pump (which can be purchased now) big power can be made. Only problem is not enough info out there right now and a lot of us tuners are still learning too. I'd say north of 500rwhp on stock fuel system with increased pressure at N/A fueling. Don't do this with boost unless you have a cam lobe at the minimal, but with any power the Z06 pump as well.

For what its worth the LT1 has 121.1 lb injectors at 2176 PSI (15MPA)
If rail pressure is increased to 17MPA that's 2466PSI and the injectors flow 137.2
2466/2176=1.133
1.133 X 121.1 =137.2
Factory Z06 injectors are 140.7 and the mechanical pump allows higher pressure than the LT1 pump, so there is A LOT of room there.

 

Whoa this has evolved into a fantastic resource to anyone in the market to go Flex fuel! I'm sure Ben will chime in once he finds some time. Looking forward to slapping a tune on, however my current tuner (Trifecta, and I have been working with them for 6+ years) hasn't been responding to my Flex fuel requests. Might have to work with someone else.

 

How do u wire it in? Thanks for all the input. And pics.

Also the length of the fuel line is about how long?

 

Finishing install now. I will have a full spread of pictures for wiring, and even GM's wire diagram broken down. Should help all of you DYI guys out there get this done the correct way

 

 

Im ready for results

 

 

Very good. Thanks for sharing the details with us.

 

First things first, I wanted to start with the wiring, and how we planned out where/how we will be getting power to the Flex Fuel sensor. We decided to use the location that the Gen5 truck motor uses. After further research within GM's truck wiring blue prints we found it to be the O2 sensor power lines.

We used the image below to help us find the correct wire. I have highlighted the most important information in the image.



This is where we will locate the wire within the fuse box:



With this information we were able to locate this wire:



We chose to not plug into the fuse port, but rather actually splice into the line. Should be much better for long term reliability purposes.



Next we needed to find a ground - Easy, found a nice bolt right next to the intake system



Wednesday we need to put it on a lift to get the single to the ECU. Based on our wiring diagrams, we chose to piggyback onto the O2 sensor on the passenger side header. Just so every knows, we have confirmed that the Flex fuel sensor is getting power, and everything is working perfectly.

Any suggestions on how to get the signal to the ECU, please feel free to share. Thanks!