WHY DOES 1984-1986 I-6 GET 18/24 (4 SPEED MAN.) BUT WHEN YOU GO TO A MORE BETTER(WV ENGLISH) FUEL INJECTION 1987-1996 (5 SPEED) IT GOES 15/19

 

Can you re-phrase please, I don't understand...

 

no idea what you are trying to ask,

 

Here I am going to guess on this one. I believe he is wondering why the carbd motors get better gas mileage than the newer and supposidly hi-tech fuel efficient EFI motors, am i right?

 

that boy needs grammar
as back woods as i am i cant under stand that

 

I suspect emissions equipment.
You can throw the 83 in with that high mileage group.
Same as 84.

 

I understood quite clearly what he meant (I'm good at cryptoquotes, too, wouldntyaknow...), except for the second parenthetical statement, which eludes me completely, maybe he's apologizing for his second-language English? Understandable, and certainly courteous of the good chap, wotwot?, (Now wherrre's my Grey Poupon?). His English is no doubt way better than my grasp of his native tongue, whatever it may be. My '86 F150, NP 435 hasn't ever gotten that kind of mileage, even when the 1-bbl and stock exhaust was on it (and the feedback system actually worked)! In fact, since the boltons went on, the mileage hasn't really dropped overall, it's still around 13/18. I think because of the lean mixture and extremely restrictive exhaust, more throttle was required to get up to speed, especially with a full load (and then the power curve fell right on its face, this needed immediate remedial attention; it simply would not do...).

I don't think those figures are quite accurate. I've seen quite the opposite, in fact. For example, the EFI I6 in a buddy's truck gets a smidge better average than mine, more (on its BEST day) like that quoted carb figure (which seems a little high, IMHO, muchlikethesourceofthosefigures ...bites typing thumb...ahh, no more cheap shots. I'm too nice for that sort of thing!) If there is ANY reason to this at all, it might be because the throttle body and exhaust manifolds of the EFI setup flow a bit more than that scrawny rodent cage stuffed onto the side of the earlier engines, but my experience has certainly not supported that conclusion all too well, now has it?

You can't really trust published mileage specs. All sorts of Enronning going on there. What's that, with a hurricane-force tailwind, coasting downhill? Due to the enormous variance in real-world driving conditions---air density, state of tune and wear, fuel quality, oil+other lubricants used, weight of foot, gear ratio, tire size, wind conditions, error factor in measurements, moon phase, and whether or not the favorite football team won the last game, never mind the manufacturer wanting to show the figures in the best light, etc., etc.---you might as well take those figures with a a grain of salt and a splash of lime.

Oh, this is spoto be fo' Expert 300 Inline Peoplez? Oops, my bad, I'll shuffle off now... now is it 300 expert peoplez in line, or do the Expert 300 be like a Fortune 500-type-bunch, or maybe it done be Expert 300 ONLINE peoplez, mo' to the point?

 

I had two carbed. 300's that got no better than 13. I guess you can count three carbed., I replaced one witha factoryrebuild and it got the 13. It's predeccessor got 10.5 andmy first 300 got 12 all the time. I had one 300 that was fuel injected in a 92 F-150 SC 4x4 (5-speed, manual) that got 17 on the highway. How did you guys get 18 out of a carbed. 300 I-6?

 

I recently posted, but I'll share again.
I just returned from a 500 mile trip, all highway, got 19.7 mpg (call it 20).
All stock, one owner, Super cab, 8 foot bed, 600# payload, 170K, 4 spd OD, 3.08 diff, 41 psi (heavy load) tires....it turns 1600 rpm at 60 mph. When it was new I'd see 21.
This is why I bought (and still drive) this truck. I knew I'd be doing alot of highway driving.

Given this, when new, with a std cab and short bed, no extra payload...you should
see at least 23.

 

With a very light foot .

 

My dad had a carbed '82 (and a very light foot). It was a 3-on-the-tree with a 2.73 rear. It got around 18/19 city and 21/23 hwy. My EFI '94/5speed/2.73 got a best ever of 19 on the hwy(with 215,000 mi.) Typically it gets 15/16 combined driving, but I DON'T have a light foot. My brother keeps telling me to not use the OD, and he thinks it'll get better (lugging too much in 5th-not efficient). I have yet to try it. One thing though, when I had the head off, it still had crosshatch in the bores. My dad's needed a rebuild by 130,000, and had broken rings/ring lands and had to be bored .030". Maybe from detonation (running too lean)? Might account for good MPG's and relatively short life.

 

I keep hearing all these stories about good fuel economy. Mine is an 84 F150 auto I6 TFI ignition ,210,000 miles new head efi manifold free flow cat 2.5", 2.5" muffler and pipes, rebuilt carb, 3:08 rear stock tires 195 75 r15, new oxygen sensor, throttle sensor, tfi module, feedback solenoid, thermostat, new EGR valve, new egr solenoid, I use the truck for weekend trips to the mountains 250 miles each way, seldom a heavy load. Best gas milage in a year 16 normal 15, pulling a 16 foot boat 12. and a very light foot.

 

I've got a 69 Ford F-250 4x4 with 33's + 4.09 gears and the best I've ever got with it was 12 with the original 1 bbl. It turns about 2500 RPMs @ 55. However, I had essetialllythe same truck (71) with the same tires and gears that had a 360 in it and that truck got 14 on several occasions. The reasoning is that since the truck with the v-8 makes it's horse power and torque at higher rpms, it wasn't working as hard as the 6 so it got better milage. If I changed the gears in my truck to lets say 3.08, my milage would improve significantly, because the engine wouldn't be working as hard and therefore would get better milage.

 

HIGH gears!! 2.73s - 3.08s

It is ALL in the gears for MPG and the 300ci.

My 84 F250 4x2 has 3.73s, 4 speed and 33" tires. Haven't yet checked the MPG, but I can say for sure that is SUCKS.

 

The carbed 84 F-150 I had had a 3.55 rear end and the 83 F-250 had a 4.10 rear end. Best I got with the 150 was 14 (barely), the 250 always got 12. It never mattered how I drove either truck, usually easy, and never closely inched towards 18. My EFI 92 F-150 SC 4x4 300 I-6 5 speed only got 17 at best with a 3.55 rear end.