I know there is a bunch of threads about this but im gonna ask some questions to make sure im on the right page. I have a 99 frc with a big cam, 243 heads, fast 102 and I know I dont really need e85 but it is very interesting to me and I just want to try it. There is only one station around me that has e85 and I drive the car so I still need to be able to use pump 93.

I have a lingenfelter walbro pump in my car and I broke the factory fuel line so the lines from the fuel filter to the fuel rail is black braided line. From what I read the factory stuff in the tank will work with e85. So all I really need is the flex fuel sensor, wire it to power/ground and to pin 56 BLUE.

So far am I correct?

Here is some things im not sure about.

What OS do I need to swap to with HP tuners? I am using the stock 12593359 OS but i have read the f-body guys use a 02 suburban OS but will that work with my car with ETC or what would be a better OS to use?

What would be the best sensor to use? Iv read you can use one out of a ford taurus easier because it is a screw in type instead of a quick disconnect type so you can use an fittings easier.

I am using stock ls2 injectors now that are about 75% duty cycle so the will not be big enough for e85 but i have some SD 60# high impedance injectors i got from a buddy. Will they work for what i want to do?

Is there anything else im missing or i am just completely wrong about?

 

......

 

nobody huh

 

Why would you even want to go there, in the first place?

 

108 octane that's cheap....

There were GMT800 trucks with drive by wire. The will the tune not work correctly if you just enable flex fuel and populate the tables?

 

there is a lot of benifits to e85 besides just the ocatane. A couple of my friends use it, one with a turbo silverado and another with a 5.0 that is not boosted on e85 but was na on e85 before and both run great on them.

03+ silverados are all drive by cable. My 07 classic silverado is drive by cable and has flex fuel tables that are not used. I know on them its as easy and adding the sensor, injectors and activating the tables but i dont know if i can just swap a OS from something newer and it work.

 

A stock 04 Z06 tune has flex fuel tables in it. I wonder if i can use that?

 

It all depends on whether or not the PCM will recognize the fuel composition sensor.

 

The reason the automakers don't want the current 10% ethanol additive requirement upped to 15 is concern over damage to various seals, etc, in the fuel system. I would expect prolonged E85 use in a non-FlexFuel vehicle to cause damage - rotting and/or cracked seals, etc. They did do a lot of work to make vehicles E85 compliant. And at the end of the day, your fuel consumption goes up, which you may of may not care about, as ethanol contains less energy per gallon than gasoline. And to get any performance gain from higher octanes, you need higher compression ratios.

 

E85 will NOT damage your stock components in a C5's fuel system. Ive been running straight E85 for years with zero signs of corrosion or deterioration in the fuel tanks and lines. I now have bigger feed lines to the motor because its making almost 1000hp crank but I still use the stock fuel line as a return. All good so far.

That being said, I dont believe its worth it outside of a forced induction setup. The cost of new injectors, fuel system components if needed and a tune wont be worth what little gains you may see on a na setup, imo. Its cooling effect and resistance to pre-ignition is best taken advantage of with boosted motors.

 

I can agree with that to a extent. I am not expecting to pick up big power na while doing this I just want to do it just to do it. About the only extra expense I will have is bigger injectors and the sensor. I do plan on going boosted later so it would be nice to have this already figured out for when I go boosted. Right now all I really need to know is if I can segment swap the engine peramiters from a 04 z06 tune into my pcm and it work? Or maybe do a whole pcm swap to a 04 z06 pcm and if so is there wiring involved or its it just plug and play?

 

All this hype that ethanol is the death of your fuel system is a lie fabricated by the oil industry. Yes ethanol fuel goes bad faster and is more likely to leave deposits if it sits for extended periods of time. But the truth of it is e85 will not hurt your vehicle if it is tuned for it and is in regular service.

 

I'm sure the oil industry is guilty of various lines fed to the public and this is pretty much a moot issue on cars that are produced after the early 2000's with regards to compatibility of the fuel system to accept ethanol fuels but the idea that ethanol can be harmful is no lie.

The danger lies in how long the fuel is allowed to sit in your fuel system. Ethanol and moisture combine together over time, 4-8 weeks not months and months or years. The combination of moisture attracted to the ethanol is the issue, many of us who let their car sit over the winter or a prolonged time are justified in their concerns. Damage to rubber lines aside I have opened carburetors and found the whitish/green deposits from the moisture, it can also be seen on some surfaces of older metal gas tanks. It's a form of moisture corrosion so just consider if you would be willing to let the small valuable parts of your fuel system that contact fuel to sit out in the weather without protection.

Again this is a non-issue for newer fuel injected cars used on a regular basis but if your fuel will sit for any period of time it's best to avoid higher levels of ethanol without some sort of consideration for the effects.

 

The car gets driven pretty regularly but it is not a daily driver unless it needs to be.

I think we are getting a little away from what i am trying to accomplish here. I completely understand the effects of running e85 all i need to know is how to integrate a flex fuel sensor into my car.

 

Another option is a stand alone controller. We're working on getting it setup and testing on my c6z right now and will be making a harness to run on the c5 as well. As long as your pump gas 93/91 ocane tune is correct and your fuel system will be able to keep up, this is a simple plug and play controller and takes about 5 min to install. It uses a gm flex fuel sensor and corrects fuel trims according to ethanol content.

Here's a dyno graph from a 06 c6z test car we are doing. The car is already setup with flex fuel (pined the factory pcm) so we have a comparison for the c6 market. The red line is the 93 octane tune, blue line is with flex fuel turned on, factory pcm adjusting for ethanol content, green line is the stand alone flex fuel controller running on the 93 tune only (flex fuel turned off on factory pcm. Even on the test car it picked up a significant amount through the mid range over the factory corrections. On the later pcm's 09+ have a flex fuel PE table you can fine tune and achieve similar gains however the earlier pcm do not have the ability which is why the stand alone picked up so much.

 

Have you made any progress with this and the C5s?