'82 F100 SWB Flareside 300 six Ford 3.03 (manual) No AC

Just bought this bag/box of rattles and it does not have a operational speedometer. The column shifter broke and it was replaced with one of those Hurst floor shifters. On an earlier F100 that I drove until it rusted to pieces ('80) the speedo drive on the transmission tailpiece was on the lower portion. On the '82 the speedo drive is on the upper portion of the 3.03 tailpiece and I can't cut a hole for the speedometer cable there. So anyway, I drive like an ol' fart and avoid trouble with the law that way. (so far so good)

I figure my mileage in a sort of approximate way; by "mapquesting" between fillups. My last highway stretch came out at 21 mpg. (Woodbridge VA to Norfolk & return)

Here in Virginia, the truck is listed as an antique (over 25 years old) and that means no more inspections of any kind.

Here are some of the things I intend to do in the near future to improve the MPG:

1. Electric cooling fan
2. a. Install headers and Clifford intake manifold
Note: There will be no way to hook up EGR and Thermactor to the new manifolds (Nor a catalytic converter)
b. Just to see how it behaves I'm thinking of leaving off the thermactor pump and corking the rubber thermactor hose leading into the stock exhaust manifold.

What will removing the thermactor pump do? I'm aware of why it's there. It adds O2 to the exhaust so more of the CO burns in the CAT. On the other hand, I'm not sure the CAT works at all on the ol' F-100 and by increasing my MPG, I orta be lowering my pollution and carbon footprint, etc.

Thanks,
BSI

 

21 mpg is pretty darn good for what you have.

I would not waste the money on the Clifford intake unless you are trying to get more performance out of it.

I wouldn't do the headers either. Late model EFI manifolds and a 2-1 exhaust would be a better bang for the buck and they are nearly as good as far as flow goes.

Once again this is assuming that you are not after more performance which will decrease mpg.

 

21 MPG is the EPA rating for this year range of trucks with the 300 I6.

You won't improve it much beyond that. Infact installing headers and the new manifolds could and most likely will hurt your mileage. Increase performance though.

Removing the EGR can and most likely will hurt your gas mileage as well. The EGR puts inert exaust gases back into the combustion chambers. Therefore less fuel from the carb has to be used between each combustion cycle. Remove the EGR, and the extra space in the cylinders from the missing exaust gasses have to be filled up with something, and that's more fuel. Can cause severe engine ping as well with it missing or inoperable.

Putting a clutch fan on the engine will help some with mileage, you might gain .5 to 2 miles a gallon.

I would not put a electric fan on one of these trucks, but I'm oldfashioned. The work you would have to do the electrical system far outweighs the benefit IMO. You can't just splice it in. You would have to upgrade the altenator, and charging system to handle it 9 time out of 10. And the extra load caused by the charging system could decrease mileage anyway.

Only other way to possibly squeeze some mileage is to have the rear end regeared, or change tire sizes.

Like I said 21 MPG is the EPA rating for the truck, I'd leave it alone if it was mine.

 

I already own the Clifford Intake Manifold. I got it for a steal on Ebay. It also came with this 2 BBL Carb (a Holley 774 ('B' or '8' can't quite make it out)) (350 cf), which needs a rebuild. I already own the headers (also Ebay). They are 2 pieces (each 3 into 1). I'll have to build an exhaust system.

If I really feather the throttle and accelerate like the old guy wearing a hat I am (It's great having the "antique" plate; everyone expects you to drive slow.) I think I ought to improve the MPG. If the butterfly(s) on the carb don't open far the fuel won't move either.

I already own the electric fan. The only hookup it needs is 12V and ground. I used it before on my '80 F100. The present mechanical fan is the type that has no clutch but the blades supposedly flatten out at higher RPMs.

The most serious hassle I think I'll be facing is adapting an Overdrive unit. I own a Laycock (identical to Gearvendors except for the serial number) 2 speed unit. It came off an old Volvo. It's supposed to replace the 3.03 tailpiece but I think that will require some fabrication.

Of course the wooden bed (or what remains of it) probably needs my attention before all of this.

BSI

 

I expect that your fuel mileage to drop to around 15 MPG with that setup. You can ask more specific questions in the inline six forum.

It's called a flex fan.

What amp altenator do you have in the truck now? 40 amp, 60 amp, 70 amp, 90 amp? And what's the amperage of the electric fan? That will tell you if you need to upgrade the altenator and electrical system or not. You will cook the electrical system if you don't have enough.