Author Topic: 5.3 Accessory Layout, DOD, E85  (Read 5919 times)

Offline Captkaos

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Re: 5.3 Accessory Layout, DOD, E85
« Reply #15 on: April 15, 2014, 08:03:36 PM »
Talking about purpose built vehicles not something you drive everyday. 

Offline Skyshadow

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Re: 5.3 Accessory Layout, DOD, E85
« Reply #16 on: April 15, 2014, 08:11:00 PM »
^OOH then VERY MUCH agree! I thought you meant "E85 badged" types as purpose built. lol

Offline SomeTexan

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Re: 5.3 Accessory Layout, DOD, E85
« Reply #17 on: April 16, 2014, 08:31:48 AM »
^ if the mapping takes advantage of the higher octane then maybe. But i don't see it happening. Plus, its not like if you put a tank of E85 that you'll suddenly see a difference. Most Owner's manuals will tell you that it takes 2-3 tanks of fuel for the ECU to fully adapt to a fuel change.

In a flex fuel vehicle, e85 is detected immediately and the computer changes to the e85 map. If it didnt, there would be a good chance of damage. It doesn't "learn" to run on e85, just a secondary map.

Spanky, if you use the dirty dingo ls swap mounts you can run all the stock ls truck accessories. The mounts are adjustable, if slid most of the way forward, it all clears. Barely.
86 swb c10, LQ4/glide with 80mm turbo

Offline Skyshadow

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Re: 5.3 Accessory Layout, DOD, E85
« Reply #18 on: April 16, 2014, 08:39:55 AM »
I understand they are dual mapped but they still have to learn the fuel characteristics. Just like how your car is currently learning as you drive it, it starts over on that task when switched to a new fuel.

Offline SomeTexan

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Re: 5.3 Accessory Layout, DOD, E85
« Reply #19 on: April 16, 2014, 09:25:27 AM »
I understand they are dual mapped but they still have to learn the fuel characteristics. Just like how your car is currently learning as you drive it, it starts over on that task when switched to a new fuel.

The computer (for flex fuel) has 2 maps. One for unleaded and one for e85. Reading knock and o2 sensors it chooses a map for the fuel it is running on. Now, those maps do learn as they go, but within limits. As someone who has spent hours tuning these engines, I can say with 100% certainty that there are 2 base maps. The engine would be damaged before it could learn to run on e85 on its own. What most people think is the truck learning e85 is the truck trying to figure out what it is running on. A couple gallons of 93 in the tank turns that fresh e85 into e70. Now, say you got a winter blend (actually e70-75) then you are running closer to e50-e60. Luckily I live near a race track that sells fuel, and there are several race classes that run spec e85 fuel. Cheaper than the pump, and it is good fuel. I have never found pump e85 that tests good.
86 swb c10, LQ4/glide with 80mm turbo

Offline SomeTexan

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Re: 5.3 Accessory Layout, DOD, E85
« Reply #20 on: April 16, 2014, 09:46:12 AM »
Forgot to mention, normally what the computer has learned for each map is stored and isn't lost when you switch fuels. But, if you are running something between e85 and pump unleaded (a few gallons of one in the tank when you fill with the other) sometimes the computer can get confused as to what it is running, and it may try both maps, and could start changing them. Not a problem if you empty the fuel system, but not many people do.
86 swb c10, LQ4/glide with 80mm turbo