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https://slantsix.org/forum/viewtopic.php?t=42952		 Page 2 of 2
Author:  ceej [ Wed Dec 22, 2010 5:23 pm ]
Post subject: 
It will run OK, but you will go through more fuel.

Without bumping compression up, you won't be able to take advantage of the 105 Octane rating of the stuff.

You will want to keep the tank topped off, and not park it for prolonged periods. The Alcohol will absorb water in a partial tank, and play heck with all the metal surfaces in the carburetor and so forth. The inside of you carb will look all fuzzy and white after a while if you aren't running it a lot. Weekly at bare minimum.

It does smell a lot better than regular though! :lol:

CJ
Author:  Ross [ Wed Dec 22, 2010 8:07 pm ]
Post subject: 
Ok thanks! :)
Author:  65CrewCabPW [ Wed Dec 22, 2010 9:50 pm ]
Post subject: 
Quote:
It will run OK, but you will go through more fuel.

Without bumping compression up, you won't be able to take advantage of the 105 Octane rating of the stuff.

You will want to keep the tank topped off, and not park it for prolonged periods. The Alcohol will absorb water in a partial tank, and play heck with all the metal surfaces in the carburetor and so forth. The inside of you carb will look all fuzzy and white after a while if you aren't running it a lot. Weekly at bare minimum.

It does smell a lot better than regular though! :lol:

CJ
have you tried putting small amounts of Marvel Mystery Oil in your fuel, when running E85?

It's cheap at WalMart, and just a couple ounces per tankfull should have a huge effect in preventing corrosion and keeping things clean and cutting down the wear in moving carb parts, fuel pumps, etc.
Author:  ceej [ Wed Dec 22, 2010 10:02 pm ]
Post subject: 
Just so you understand. When you jet up for E-85, if you were getting 20 mpg, your going to land somewhere closer to 14 mpg at Stoich for this fuel. Jets need to be sized ~30% bigger.
9.7:1 is a normal operating A/F ratio for E-85.
Max power is achieved somewhere around 6.7-7:1 A/F ratio. 11:1 is lean.
For a regular gasoline engine, E-10 not considered, 14.7:1 is normal. Power is good at 12.5:1 range or so and lean burn is out around 17:1 for most of the older engines. Some newer lean burn technologies can exceed that.
This means : Your going to be spending more time filling up.
A/F meters won't operate normally with E-85. Digital Lambda meters can be calibrated to read "Desired Stoich" though.

I have an idea that E-85 could dip you down to 10 mpg, or less. Without additional compression, it's not going to equate to additional power.

Think about that before making a permanent change.

With additional compression, you can decrease that 30% drop in economy. I don't know that I'd make the move for 20-26% less economy in a street rig though.

Flex-Fuel vehicles can improve on the 26% figure by a bit, as they run fuel injection systems and computers to gain maximum benefit. Post 2003 production claims better, but actual figures still seem to support those figures though.

The advertised 105 Octane is innaccurate. Actual is closer to 94-96 (R+M)/2 . E-85 will tolerate compression ratios that are higher than Premium fuel is capable of, so there is power to be found with alternative fuels like this one.

For passing an emmission test, maybe. For driving, not so much. Stations that sell E-85 are kinda far apart. Nothing like re-jetting on the side of the road to get home. :lol:

2¢

CJ
Author:  emsvitil [ Wed Dec 22, 2010 10:11 pm ]
Post subject: 
E85 isn't always E85

It's E75 to E85, so correct jetting would be impossible.

You need a sensor to determine the E level, and fuel injection smart enough to compensate.
Author:  Ross [ Wed Dec 22, 2010 10:21 pm ]
Post subject: 
Psh as of right now i get about 11 mpg. I dont wanna go down to like 5 mpg. I wasnt considering converting it to flex fuel because i dont really want to tear into the carb or anything. I was just curious. But thanks though. anyone know how i could get better fuel mileage.

This is kind of off topic but does anyone know how i could fix my fuel gauge? it tells you when there is Full 3/4 and 1/2 but once it falls below half it drops straight to E.
Author:  Reed [ Wed Dec 22, 2010 10:32 pm ]
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Sounds like you have the typical old mopar gas gauge problem. Start by verifying the ground strap is correct, then check the voltage regulator on the back of the instrument panel, then you need to check the output of the actual sending unit. I don't know the correct values off the top of my head, but a factory service manual or one of the more knowledgeable guys on the board can tell you.

To get better gas mileage get your vacuum hoses and ignition timing all sorted out. You might be surprised at how well the truck runs once you get it back up to stock operating levels. If I were you, I would try and get the truck running as good as possible in stock form before I went changing anything around (except maybe dumping the EGR and removing the catalytic converter).
Author:  Ross [ Wed Dec 22, 2010 10:39 pm ]
Post subject: 
Ok thanks Reed. You've helped a LOT!! ill let you know if i have anymore questions later on. Ill see about taking the egr system out tomorrow and let you know how it runs. Hopefully much better.
Author:  wjajr [ Thu Dec 23, 2010 5:03 am ]
Post subject: 
For my 67 Dart, and most likely your truck’s fuel gage resistance:
Empty = 73 ohms +/- 12 ohms
Full 9.6 ohms +/- 1 ohm

Disconnect wire from gage at tank, set VOM to 0-100 ohm scale measure resistance between electrode of sending unit and ground. VOM should read within the above high & low ohms (6 to 85 ohms) depending on how much fuel is in tank.

I have installed a secondary grounding conductor between the gas tank & frame. Some here say that dose nothing, however I don’t believe the metal ground strap/clip connecting sending unit to metal fuel line provides the best long lasting ground. There is too much of a chance for rust to corrupt the integrity of the circuit over time, increasing “in series resistanceâ€￾ of this circuit. This grounding method relies on all the clips that hold the fuel line to the undercarriage to complete this circuit.

Another reason for your fuel gage to stop reading at and below ½ tank could be due to corroded or coated with crud resistance coil on the sending unit. There is a resistance coil that a conductor rides on as the float moves from full to empty. If the electrical connection is interrupted because that coil is dirty, no electrons will flow, and the fuel gage will stop reading. This can be caused from long standing fuel sitting in the tank during storage of the vehicle.

I had this crud build-up happened to my 82 LeBaron’s sending unit one winter that I did not fully fill its tank, and now reads empty from top-off until about 1.5 gallons are consumed, at which point the gage indicates fuel level correctly.
Author:  Ross [ Thu Dec 23, 2010 5:42 pm ]
Post subject: 
So i took the instrument cluster out and figured that there is a light blue wire with a black stripe for the fuel gauge. where is the first place that it goes? the fuse box?
Author:  Reed [ Thu Dec 23, 2010 5:57 pm ]
Post subject: 
If I remember right, the first stop for this wire is the sending unit in the gas tank.
Author:  Ross [ Thu Dec 23, 2010 6:08 pm ]
Post subject: 
Oh hmm. I followed it and it goes to the fuse box. But it goes to the first fuse which is 30 amps, which is for the heater blower moter. My owners manual says it's supposed to go to fuse 12 which is 3 amps. I'm confused.
Author:  Reed [ Thu Dec 23, 2010 8:05 pm ]
Post subject: 
Here is the wiring diagram from the inside bulkhead connector to the taillights of an 84 Dodge van, which should be near identical to your 1982 truck.

Image

Image

Image

Image

As I read it, the fuel sending unit wire (designated F12 18LB) goes straight from the sender to the dash gauge, at least on the 84 van.
Author:  Ross [ Thu Dec 23, 2010 10:37 pm ]
Post subject: 
Thanks for the diagrahms. It was a little hard for me to fiure what wire it was on the connector. Ill take a look at it sunday maybe.
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