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testing predator and flex fuel engine

jcollin160

Full Member
Joined
Feb 16, 2006
Messages
132
Location
curwensville, pa
i couldnt take it anymore, i ordered my predator and will have to see if it will work with the flex fuel. Heres what we are testing. 2006 AV, 5.3L, 3.42 rears, predator model U-7192, Airaid cold intake, Flowmaster Super 40 muffler. Diablo says their unit is compatible, plus after some research i found you can get a custom tune with the same unit. i talked to jesse bubb for a PCM and he wouldnt do it for flex fuel and he had no chips for a 2006, westers wanted $595.00 using my factory chip and nelson wouldnt call me back.  Superchips said they havent tested it yet so dont try it, hypertech said they havent tested it yet but go ahead and install it and tell us if it works! (i hope with that kind of answer, everyone will think twice about buying a hypertech, i will never by their product).  My flowmaster is installed, airaid goes in friday and hopefully i will have the cheap tank of gas out by saturday, get a premium fill up, install the predator and cross my fingers it works....
 
Great research !!!

Looking forward to hearing more.


Keep up the great work.


I don't have a Flex-Fuel, but if you need some help with anything just ask.
 
Jc

I have been running the predator performance tune on my flex fuel AV using premium gas since Oct.  I havent had any problems at all.  I do like the increase in performance it gives  >:D

So dont worry about anything but pay the price of premium gas  :mad: and enjoy  :love: 
 
i am glad to see someone is already running this. did you have to change any parameters or did you use use the original predator settings.
 
you can still buy regular engines, this was the only flex fuel vehicle they had on the lot, my local dealer doesnt have any and never had one, i am a little worried if i go for engine work that their mechanics my not be trained.
 
Running JB in my flex fuel with no problems. Just no corn to burn around here ???
 
jcollin160 said:
i am glad to see someone is already running this. did you have to change any parameters or did you use use the original predator settings.

I didnt change a thing.
 
When I bought my truck a couple of weeks ago flex fuel engines were all I saw.
"GM is currently the largest producer of E85 flexible fuel vehicles in the United States, with more than 1.1 million vehicles on the road and with vehicles available for sale in all 50 states.
                                                e85                      gas
Combined EPA mileage       12 mpg               16 mpg
Combined EPA consumption 19.6 l/100km 14.7 l/100km
Annual GHG emissions (EPA) 8.5 tons 11.7 tons

The engine and fuel system in a flex-fuel vehicle must be adapted slightly to run on alcohol fuels because they are corrosive. There must also be a special sensor in the fuel line to analyze the fuel mixture and control the fuel injection and timing to adjust for different fuel compositions.

# Gain increased horsepower for better engine performance because E85 ethanol fuel has a higher octane rating than premium gasoline
# Lessen engine wear


E85 is a higher performance fuel with an octane rating of 105-110. E85 users will notice a mileage and range reduction of 10%-30% because a gallon of ethanol contains only 70% as much energy as a gallon of gasoline"

Wow I had never even checked out the flex fuel part. With so many on the roads I wouldnt think that the dealership would have a problem working on them. Besides from what I have found they arent much diffrent.
About 25% less fuel economy but lower emisions, and made here versus overseas. And 105-110 octane--hmmm I might have to try a tank:)  There are a lot more gas stations around me that carry e85 than I would have thought. Almost all the Spinx stations in my area carry it.

Like I said my predator is working fine in my flex fuel truck on gas. And at 105-110 octane I think as soon as this tank of gas is gone I might just be able to tell you if it works with e85 and what kind of performance gain I get with it:)
 
installed predator today, everything went fine. i towed a trailer today also, seemed like it hit a higher rpm until it shifted (good thing). i also noticed that the radiator fans stay on alot, it is in the 20's here and both fans were running. is that normal? otherwise it seems good.
 
I filled up with e85 today to give it a try. So far so good. If anything it feels a little stronger. The e85 is 115 octane so maybe it is . I put about 70 miles on it today and my mpg dispal says I'm getting about .2 mpg less than I did on the last tank of premium. But we will see what it says after a whole tank. No problems with the predator on the 93 octane program and the e85 so far:)
 
i talked to a predator tech yesterday, he said my fan setting must be off, they are going to make me a custom program and send it by email. the predator is nice like that, you dont have to send the unit back for a custom tune.
 
Ok, I have looked and this is one of the few posts that have the information in it that I was looking for, but it is really old.

I just purchased an 08, it has the GM performance Intake, GM Performance Exhaust and has been tuned with the Predator which came with the truck.  It is also a Flex Fuel truck.

Question, what fuel should I be running in this thing?  I haven't put a full tank in it yet and to be honest, it doesn't seem to run as well as my Sierra.  I did put in $50 worth of Mid grade right after I picked it up, but was looking for recommendations on if I should be running premium or finding the E85.

Thanks
 
Depends on PRedator TUNE..

as they can be set for 87 or 93 octane.
 
Here is a trick I learned from a Custom Tuner:

Mix 1 part E85 to 4 or 5 parts 87, 89, or 91 (the 91 sold in the US sucks since they removed MTBE from the blend a few years back)

What you end up with is a true 91.5 to 93 octane fuel, which is far less corrosive than E85 (regardless of E85/Flex fuel certified engine/system.

a true 91-93 octane fuel prevents knocking/preignition, and allows the ECU to use the higher performance spark and A/F ratio tables, rather than retarding the timing and dumping more fuel in to prevent the knocking (the ECU "hears" knocks way before they are loud enough for us to hear them).

That all being said...if you have an ECU or Tune based on 87 octane, you wont get much of anything from E85 or a Blend to 91-93 octane because the ECU doesnt even have the spark timing or A/F tables to adjust up to that level.

Also...trying to run higher octane in a vehicle with a tune and engine that is designed for only 87 may actually reduce performance, and the reason is because high Octane fuels ignite at a higher compression/temp than 87-89 octane, and so the engine will be expecting fuel to ignite at a certain time, but the actual ignition will be delayed ever so slightly...so if you go this route, make sure you have a tune with tables to allows for running 91+ octane.

Ron69 said:
When I bought my truck a couple of weeks ago flex fuel engines were all I saw.
"GM is currently the largest producer of E85 flexible fuel vehicles in the United States, with more than 1.1 million vehicles on the road and with vehicles available for sale in all 50 states.
                                                e85                       gas
Combined EPA mileage       12 mpg                16 mpg
Combined EPA consumption 19.6 l/100km 14.7 l/100km
Annual GHG emissions (EPA) 8.5 tons 11.7 tons

The engine and fuel system in a flex-fuel vehicle must be adapted slightly to run on alcohol fuels because they are corrosive. There must also be a special sensor in the fuel line to analyze the fuel mixture and control the fuel injection and timing to adjust for different fuel compositions.

# Gain increased horsepower for better engine performance because E85 ethanol fuel has a higher octane rating than premium gasoline
# Lessen engine wear


E85 is a higher performance fuel with an octane rating of 105-110. E85 users will notice a mileage and range reduction of 10%-30% because a gallon of ethanol contains only 70% as much energy as a gallon of gasoline"

Wow I had never even checked out the flex fuel part. With so many on the roads I wouldnt think that the dealership would have a problem working on them. Besides from what I have found they arent much diffrent.
About 25% less fuel economy but lower emisions, and made here versus overseas. And 105-110 octane--hmmm I might have to try a tank:)  There are a lot more gas stations around me that carry e85 than I would have thought. Almost all the Spinx stations in my area carry it.

Like I said my predator is working fine in my flex fuel truck on gas. And at 105-110 octane I think as soon as this tank of gas is gone I might just be able to tell you if it works with e85 and what kind of performance gain I get with it:)
 
ygmn said:
Depends on PRedator TUNE..

as they can be set for 87 or 93 octane.

It is running the predator tune it has the option to tune for 85 I think when I looked. What really sucks is there are not many stations around here in Washington with E85. Went to the closest one last night and the pumps with E85 were broke :(
 
arizona-dave said:
Here is a trick I learned from a Custom Tuner:

Mix 1 part E85 to 4 or 5 parts 87, 89, or 91 (the 91 sold in the US sucks since they removed MTBE from the blend a few years back)

What you end up with is a true 91.5 to 93 octane fuel, which is far less corrosive than E85 (regardless of E85/Flex fuel certified engine/system.

a true 91-93 octane fuel prevents knocking/preignition, and allows the ECU to use the higher performance spark and A/F ratio tables, rather than retarding the timing and dumping more fuel in to prevent the knocking (the ECU "hears" knocks way before they are loud enough for us to hear them).

That all being said...if you have an ECU or Tune based on 87 octane, you wont get much of anything from E85 or a Blend to 91-93 octane because the ECU doesnt even have the spark timing or A/F tables to adjust up to that level.

Also...trying to run higher octane in a vehicle with a tune and engine that is designed for only 87 may actually reduce performance, and the reason is because high Octane fuels ignite at a higher compression/temp than 87-89 octane, and so the engine will be expecting fuel to ignite at a certain time, but the actual ignition will be delayed ever so slightly...so if you go this route, make sure you have a tune with tables to allows for running 91+ octane.

What about marine fuel without the ethanol?  I filled up with premium last night when I couldn't get E85.  I will see how it runs.
 
Just bought my first Avy.  I think best truck ever owned and I have had a bunch,was in auto business for 40 yrs,so I have had about ever one you can think of.hope can say the. Same think in a year from now.retired so just a toy for me. 
 
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