Ford F834 Posted February 2, 2018 Share Posted February 2, 2018 "David, do you know if your son's truck had the fuel economy package? I'm curious what this consisted of, and whether the emissions label to the left of the hood latch is the same as trucks that did not have the package. When you say that yours does better on the highway, do you mean better mpg or better driving characteristics because of the power band?" I am not certain regarding the fuel economy package, but I bet it was "born" that way. It originally had 2.47 rear gears and came with the small air dam attached to the front bumper. At one time [prior to gasohol], it would return 26+ mpg [flat highway] @ 65 mph. His gas mileage now is ~22 mpg on the highway [larger tires, 3.55 rear gears and gasohol]. The front "spoiler" is now missing. I once did a short term comparison using my truck to compare with and without the spoiler. As best I could tell, the spoiler was worth about 1/2 mile per gallon increase. This was on my normal weekly route. On the highway, the 1984 [son's truck], seems just a little bit "tight" @ 70 mph. Some engine noise, where as with my 1986, the engine is still in its "happy zone". When his is returning ~22 mpg, mine would be @ 23 or so. Thanks David! It sounds like the '84 probably did have the economy package. I seem to recall tall gears, chin spoiler, and the upshift indicator being on the list. They just recently rebuilt the Maverick gas station down the road from my house, and they now sell alcohol free "clear gas" with its own special blue pump handle. This is the first time I have seen this. It is 87 octane. I wonder if the additional cost of the fuel would be recovered in increased mpg? Link to comment Share on other sites More sharing options...
1986F150Six Posted February 2, 2018 Author Share Posted February 2, 2018 Thanks David! It sounds like the '84 probably did have the economy package. I seem to recall tall gears, chin spoiler, and the upshift indicator being on the list. They just recently rebuilt the Maverick gas station down the road from my house, and they now sell alcohol free "clear gas" with its own special blue pump handle. This is the first time I have seen this. It is 87 octane. I wonder if the additional cost of the fuel would be recovered in increased mpg? The 1984 does have the upshift indicator bezel on the left side of the dash, but was not equipped with a light or associated wiring/vacuum lines. In my limited testing experience and with what our local vendors charge for non-alcohol gasoline, I do not think one will gain enough mileage to offset the price difference. By the way, Gary uses nothing but the alcohol free gasoline @ Mr. Bass station... https://www.facebook.com/pages/Mister-Bass/134170459968005 Link to comment Share on other sites More sharing options...
Gary Lewis Posted February 2, 2018 Share Posted February 2, 2018 Thanks David! It sounds like the '84 probably did have the economy package. I seem to recall tall gears, chin spoiler, and the upshift indicator being on the list. They just recently rebuilt the Maverick gas station down the road from my house, and they now sell alcohol free "clear gas" with its own special blue pump handle. This is the first time I have seen this. It is 87 octane. I wonder if the additional cost of the fuel would be recovered in increased mpg? I think the only way to find out what pure gas does in your vehicle and your driving style is to try it. There are just way too many variables. This site says "The stoichiometric air-fuel ratio for pure gasoline is 14.7 approximately, and that of the ethanol-gasoline and butanol-gasoline blended fuel should be less than 14.7." So, to actually get a complete burn and attempt to use all of the energy in the fuel the AFR should be adjusted. However, it says later that "The oxygen in ethanol and butanol gives an additional assistance to achieve lean burning in the engine". That would suggest that you can run the AFR leaner on a blended fuel than you can with pure gas, so even w/o adjusting the AFR the engine should still run acceptably, albeit with less power. But, does the leaner mix offset the loss of power? In a carb'd engine the air/fuel ratio will vary by each and every vehicle as well as each and every day since the temp and barometric pressure will have changed. And, how far you are into the enrichment circuit will vary by driver and location - if not his/her mood. So, it is a very complex equation and can probably only be solved by mere mortals via empirical data. Link to comment Share on other sites More sharing options...
1986F150Six Posted February 2, 2018 Author Share Posted February 2, 2018 I think the only way to find out what pure gas does in your vehicle and your driving style is to try it. There are just way too many variables. This site says "The stoichiometric air-fuel ratio for pure gasoline is 14.7 approximately, and that of the ethanol-gasoline and butanol-gasoline blended fuel should be less than 14.7." So, to actually get a complete burn and attempt to use all of the energy in the fuel the AFR should be adjusted. However, it says later that "The oxygen in ethanol and butanol gives an additional assistance to achieve lean burning in the engine". That would suggest that you can run the AFR leaner on a blended fuel than you can with pure gas, so even w/o adjusting the AFR the engine should still run acceptably, albeit with less power. But, does the leaner mix offset the loss of power? In a carb'd engine the air/fuel ratio will vary by each and every vehicle as well as each and every day since the temp and barometric pressure will have changed. And, how far you are into the enrichment circuit will vary by driver and location - if not his/her mood. So, it is a very complex equation and can probably only be solved by mere mortals via empirical data. During the "gas run" between Blue [at that time, Big Blue] and "Little Red", both trucks consumed the non-ethanol enriched fuel from the same pump. Link to comment Share on other sites More sharing options...
Gary Lewis Posted February 2, 2018 Share Posted February 2, 2018 The 1984 does have the upshift indicator bezel on the left side of the dash, but was not equipped with a light or associated wiring/vacuum lines. In my limited testing experience and with what our local vendors charge for non-alcohol gasoline, I do not think one will gain enough mileage to offset the price difference. By the way, Gary uses nothing but the alcohol free gasoline @ Mr. Bass station... https://www.facebook.com/pages/Mister-Bass/134170459968005 David - That is very true for when I'm "local". But, I have ~17K miles on the 2015, and almost all of the miles have been accrued elsewhere, like the trip the Grand Canyon with the boat, the trip to Florida to get Big Blue, and the vacation a year ago to Colorado. So I've used a wide variety of fuel in it, from pure gas when I can get it to ethanol-blended fuels when I can't. And I can't easily tell the difference in MPG. Having said that, I can tell a big difference when towing in the octane of fuel used. This fits with what the owner's manual says about fuel, as it suggests using higher octane while towing. I saw between 10% and 20% better MPG with 91 or 92 octane than with 87 octane, and while the math doesn't say that the increased MPG is a no-brainer with the additional cost, when you are getting ~10 MPG you'll pay the difference not to have to stop that often. Link to comment Share on other sites More sharing options...
85lebaront2 Posted February 2, 2018 Share Posted February 2, 2018 I think the only way to find out what pure gas does in your vehicle and your driving style is to try it. There are just way too many variables. This site says "The stoichiometric air-fuel ratio for pure gasoline is 14.7 approximately, and that of the ethanol-gasoline and butanol-gasoline blended fuel should be less than 14.7." So, to actually get a complete burn and attempt to use all of the energy in the fuel the AFR should be adjusted. However, it says later that "The oxygen in ethanol and butanol gives an additional assistance to achieve lean burning in the engine". That would suggest that you can run the AFR leaner on a blended fuel than you can with pure gas, so even w/o adjusting the AFR the engine should still run acceptably, albeit with less power. But, does the leaner mix offset the loss of power? In a carb'd engine the air/fuel ratio will vary by each and every vehicle as well as each and every day since the temp and barometric pressure will have changed. And, how far you are into the enrichment circuit will vary by driver and location - if not his/her mood. So, it is a very complex equation and can probably only be solved by mere mortals via empirical data. I do know that contrary to what the government claims, the ethanol enriched gas gives about 5% less fuel mileage as non-ethanol gas. Non-ethanol gas also doesn't rot everything it gets near as seen here: Link to comment Share on other sites More sharing options...
1986F150Six Posted March 7, 2018 Author Share Posted March 7, 2018 Some of you have read previous threads where I have shared gas mileage figures. For years, I have driven what is a repeatable and consistent route during the week. This is to and from work plus weekend driving. For the most part, this is 25, 35 and 45 MPH with numerous stop signs and traffic lights. There is a 6 mile non-stop stretch which is 45 MPH and I drive that 2X a day. Regarding the "repeatable and consistent route"... I was cleaning out my bill fold and found the last 3 gasoline receipts for the Pontiac Aztec and the 3 tanks returned: 21.17, 20.91 & 21.38 mpg. Link to comment Share on other sites More sharing options...
Gary Lewis Posted March 7, 2018 Share Posted March 7, 2018 Some of you have read previous threads where I have shared gas mileage figures. For years, I have driven what is a repeatable and consistent route during the week. This is to and from work plus weekend driving. For the most part, this is 25, 35 and 45 MPH with numerous stop signs and traffic lights. There is a 6 mile non-stop stretch which is 45 MPH and I drive that 2X a day. Regarding the "repeatable and consistent route"... I was cleaning out my bill fold and found the last 3 gasoline receipts for the Pontiac Aztec and the 3 tanks returned: 21.17, 20.91 & 21.38 mpg. Assuming that all three fillups took the same amount of gas, that's an average of 21.15 MPG, with a deviation of .09%, 1.1%, & 1.1%. Extremely close! Link to comment Share on other sites More sharing options...
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