Why our cars get bad fuel milage

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Well guys, this has been an interesting revision of a post I put up over a year ago as a bit of a joke, but it's taken on a whole new life. It was never meant to be serious and even I have added to it with some serious stuff.
However, the bottom line is; do we really care that much about milage, or more about "smilage". For sure gas is not cheap anymore and to those of us on (very) fixed incomes, we do drive our Mustangs a bit less, but boy, when we do, who the hell cares.
 
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Well guys, this has been an interesting revision of a post I put up over a year ago as a bit of a joke, but it's taken on a whole new life. It was never mean to be serious and even I have added to it with some serious stuff.
However, the bottom line is; do we really care that much about milage, or more about "smilage". For sure gas is not cheap anymore and to those of us on (very) fixed incomes, we do drive our Mustangs a bit less, but boy, when we do, who the hell cares.
Well, it all depends on what kind of driving you want to do. For the drag guys or the Friday night car show crowd, mileage may not be the point. I have a different set of considerations that keep me from planning a hp build. I like to drive my cars, not a little bit, but a lot.
Every year I drive up to Springfield (IL, but does it matter? I think everyone has Springfield 2 hours away!) for the Route 66 festival. Once in the Opel, but lately in the 08 GT. I would love to drive the 71 up there someday. Then again, KC, Chicago, Indianapolis, Memphis, Nashville, etc. are all within a 5 hour drive. So, building for a comfortable 6 hour drive at modern highway speeds (80+) with A/C and not draining the tank every 2 hours sounds great to me. And not being deaf when I get there!

As mentioned in the 351C Build topic, the 89 GT was a 3500lb car and got low 20s on the highway. Probably at the tested 55mph, but not a bad target. With a 13gal tank (the Opel has a 13 gal, the Safari van had/has a 17 gal/27gal, both of those and the 08 GT tend to average 20mpg. I think the 71 has 17gal?), that just gets me to Chicago.
The AOD and the T5 have steeper 1st gears than the old C4/C6, so even 3.00 or 3.25 will feel a little more perky.
Of course the old 5.0 was fuel injected, but build for decent low rpm torque (not that a stock M-code doesnt already beat the 5.0 on that point), smaller carb, and all the other 'efficiency' tricks and it may balance out depending on the right foot. All the stuff Spike talked about.
My 71 is a standard sportsroof with the 351 4v, power steering, power brakes, a/c, so it may be a couple hundred pounds less than a fully optioned Mach or Grande. 3200-3300lbs? With headers, aluminum intake, aluminum wheels, maybe another 100lbs less.

Keep weight and rpm down, intake manifold vacuum high and stay behind a semi....and enjoy hours of driving, not quick sprints around the block or up to the Qwiki-Mart where you don't get to enjoy all the high performance parts!

My opinion....your mileage may vary!
 
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Boats are expensive for sure. I've not owned a "big boat", but at least the one I had was trailered and I could buy gas at a gas station for 59 cents/liter in 1989! That boat could run all day pulling water skiers for 25 bucks.
As for you only using 1 tank a year........... you definitely need to get out and drive more, just sayin.
And to be clear, I don't really care about milage, but I do care about being ripped off by greedy oil companies, high taxes on fuel and being lied to in the process.
I would love to go cruising more but I have health issues which prevent me from doing so. But I enjoy just pulling her out of the garage and looking at her. I do take her to my mechanic to have work done. Only 3 more jobs to do and knock on wood all the big jobs will be done. I have a leaking wheel seal on left rear and while that’s being done I’m having the rear brakes replaced. And then I’m gonna have the leaf springs replaced. After there done I’ll have a complete suspension rebuild and new brakes all the way around. The heater core and blower motor has been replaced along with a whole bunch of smaller work. The body and interior are original and don’t need anything done. The motor and transmission work great. I’m praying I’m still around to have this work completed. But I take comfort in the fact that I have been a good caretaker of this car and the next caretaker will be getting a great car. I’ve suffered with severe back problems and now my heart is taking a crap on me. For those of us old enough to remember rose Anna rose Anna danna from Saturday night live she was right . She would always say it just goes to show you there’s alway something.
 
I would love to go cruising more but I have health issues which prevent me from doing so. But I enjoy just pulling her out of the garage and looking at her. I do take her to my mechanic to have work done. Only 3 more jobs to do and knock on wood all the big jobs will be done. I have a leaking wheel seal on left rear and while that’s being done I’m having the rear brakes replaced. And then I’m gonna have the leaf springs replaced. After there done I’ll have a complete suspension rebuild and new brakes all the way around. The heater core and blower motor has been replaced along with a whole bunch of smaller work. The body and interior are original and don’t need anything done. The motor and transmission work great. I’m praying I’m still around to have this work completed. But I take comfort in the fact that I have been a good caretaker of this car and the next caretaker will be getting a great car. I’ve suffered with severe back problems and now my heart is taking a crap on me. For those of us old enough to remember rose Anna rose Anna danna from Saturday night live she was right . She would always say it just goes to show you there’s alway something.
I'm sorry to learn of your ongoing health issues and I applaud your commitment to get your car finished and hopefully get to enjoy it for sometime to come.
 
My Q ode '72 convertible with the C6 and 3.25 gears gets about 12-14 highway MPG at 80 MPH on the interstate. I found a D1ZX-DA intake a few years back and put it on with a 750 vac secondary Holley. I picked up about 2 MPG and the pull is smooth and just keeps coming. Hated that damn 4300D carb, it was so damn finicky.

My '72 Mach 1 has a Pair of '71 M code heads and cam, Hooker SC headers, 750DP, CJ converter with a street strip custom C6, 3.89 gears, 31 spline Detroit Locker, nodular 3rd member and 12" wide rear tires at 26" diameter. Milage is, well, stupid terrible, but it launches hard and shifts at 6300RPM at WOT. I guess the 550+ inch big block I'm building for it with P51D heads will get negative MPG!!! 🤪
 
Tom, add a trailer hitch and pull an auxiliary fuel tank!! You could make it look like the back end of your Mustang.
You know....on a side note....a 71/73 Mustang trailer using the front clip and full hood blended with the last foot of the 71/73 might actually be pretty cool. And have the hood open like normal.
 
You know....on a side note....a 71/73 Mustang trailer using the front clip and full hood blended with the last foot of the 71/73 might actually be pretty cool. And have the hood open like normal.
Hmm, would you pull it forward (like a normal car) or backwards and really confuse everybody.
 
Hmm, would you pull it forward (like a normal car) or backwards and really confuse everybody.
At stoplights, I can see the person behind you trying to swerve out of your way!
 
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