fuel milage
Posting Guru
Joined: Dec 2007
Posts: 1,061
Likes: 2
From: London, Ontario Canada
i would put a K&N air filter and clean the carb or get a new carb and intake, aluminum with better flow, and less weight, and take off any ac compressors, keep tire pressure up and grease or replace wheel bearings and change the fluid in rear end, and flush it if ya have to, and do the same for tranny and engine, and get a msd box, new spark plug wires and cap and rotor, and clean the points, and a high output spark coil for better bang and put a K&N oil filter on, and clean the truck regularly and waxed it like a baby's butt, so ya can cut through the wind with less Resistance. And drive at posted speeds, and coast to red lights, and you could research hydrogen box thing, it adds to the fuel mixture, hard to believe but i know someone who did a 80's caprice and says it works, i have to see it first. best of luck,
Senior User
Joined: Apr 2008
Posts: 171
Likes: 0
This 70 f100 4x4 I got, my dad swears he was getting 19 mpg with it. your mpg's are going to be affected with your driving habits as well as maintenance. I know this truck I got gets better than my dodge, my dodge gets about 7 mpg, and that's driving it nicely.
Post Fiend
Joined: Nov 2000
Posts: 6,060
Likes: 7
From: Glendale Arizona
I get around eight with my 69 Crew Highboy if i run the freeway to work, if i run the side streets and maintain 45 i can get almost 14. A huge difference on the 360.
I also personally followed the most frugal FE i have ever seen. One of our FTE members pulled over 22 MPG out of a 65 F100 352 3.25's and three speed over 1200 miles from PA to Iowa. I followed behind with my 300 six and best i could pull was around 20 to the gallon. Another FTE member pulls well over 20 in a 66 with a 240 and 3.0 gears proven on the 600 miles to the Supernats on Knoxville.
Christine A 64 F100 gets around 16 to the gallon with 472 cubic inches and EFI, A C6 and 2.75s, and Zero lead footing.
Garbz
I also personally followed the most frugal FE i have ever seen. One of our FTE members pulled over 22 MPG out of a 65 F100 352 3.25's and three speed over 1200 miles from PA to Iowa. I followed behind with my 300 six and best i could pull was around 20 to the gallon. Another FTE member pulls well over 20 in a 66 with a 240 and 3.0 gears proven on the 600 miles to the Supernats on Knoxville.
Christine A 64 F100 gets around 16 to the gallon with 472 cubic inches and EFI, A C6 and 2.75s, and Zero lead footing.
Garbz
Ford Parts Specialist
Joined: Nov 2006
Posts: 88,826
Likes: 784
From: Simi Valley, CA
EVERYone that owns any Ford truck needs this guy to stop by his house!
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Fleet Mechanic
Joined: Aug 2002
Posts: 1,344
Likes: 12
From: Sioux Falls SD
25mpg seems to be a little stretch, but I do know they can get 20mpg.
I have a friend that has a 70 F100 390 FE and four speed. was getting 10-15 tops. Clutch went out of one of his other cars and he was being towed home in it with his wife driving the truck. He said his eyes were burning up from the way rich fuel mix.
Rejetted the carb and good tune up now 55 mph can get 18mpg with stck gear, not sure what ratio.
I have a 1965 F100 with the 300 6 and four speed. With the stock 3.50 gear and 235R75/15 tires. 55mph yielded 13mpg.
I swaped the 3.50 for a 2.75 and recalibrated the speedo. Now I get 18-21mpg at 60mph and my 300 pulls better to boot. Creeper is now usable and I can run upto 55mph in third now when towing.
Truck is much more flexible. I get easy 15mpg around town stop and go.
If the 289 is set up for torque, a 2.75 could work. 3.00 for sure.
Biggest thing is speed. Thease trucks are brick walls for aero.
FYI my 65 weighs 3900# with half tank of fuel.
I have a friend that has a 70 F100 390 FE and four speed. was getting 10-15 tops. Clutch went out of one of his other cars and he was being towed home in it with his wife driving the truck. He said his eyes were burning up from the way rich fuel mix.
Rejetted the carb and good tune up now 55 mph can get 18mpg with stck gear, not sure what ratio.
I have a 1965 F100 with the 300 6 and four speed. With the stock 3.50 gear and 235R75/15 tires. 55mph yielded 13mpg.
I swaped the 3.50 for a 2.75 and recalibrated the speedo. Now I get 18-21mpg at 60mph and my 300 pulls better to boot. Creeper is now usable and I can run upto 55mph in third now when towing.
Truck is much more flexible. I get easy 15mpg around town stop and go.
If the 289 is set up for torque, a 2.75 could work. 3.00 for sure.
Biggest thing is speed. Thease trucks are brick walls for aero.
FYI my 65 weighs 3900# with half tank of fuel.
Senior User
Joined: Jan 2008
Posts: 457
Likes: 0
From: Burleson,Tx
Simple recipe for 32.4 mpg's in a 67 F100 short bed. add 1 1990 isuzu 3.9L diesel 4 cylinder engine, 4 spd 700R4 automatic, 3.27 limited slip 8.8 rear axle and good year 225/60/18 tires.
A very simple reliable combo that nets and honest 32.4 mpg's with over 60% city driving and not babying it at all. I also have more performance than a 2008 dodge 2500 with cummins diesel so I know its got more performance than a stock 289( I used to have in my 66 mustang). Oh yeah you can also run this on used vegi oil for around 10 cents a gallon after filtering. :d
A very simple reliable combo that nets and honest 32.4 mpg's with over 60% city driving and not babying it at all. I also have more performance than a 2008 dodge 2500 with cummins diesel so I know its got more performance than a stock 289( I used to have in my 66 mustang). Oh yeah you can also run this on used vegi oil for around 10 cents a gallon after filtering. :d
Ford Parts Specialist
Joined: Nov 2006
Posts: 88,826
Likes: 784
From: Simi Valley, CA
Simple recipe for 32.4 mpg's in a 67 F100 short bed. add 1 1990 isuzu 3.9L diesel 4 cylinder engine, 4 spd 700R4 automatic, 3.27 limited slip 8.8 rear axle and good year 225/60/18 tires.
A very simple reliable combo that nets and honest 32.4 mpg's with over 60% city driving and not babying it at all.
A very simple reliable combo that nets and honest 32.4 mpg's with over 60% city driving and not babying it at all.
No.
Consider how much gasoline one could buy for the 1000's of dollars spent for this swap.
Here in SoCal, diesel costs more than 91 octane premium gasoline. The average price for diesel is $5.07 a gallon.
Last time I filled up, premium was $3.97 a gallon. Regular was $3.57 a gallon.
Senior User
Joined: Jan 2008
Posts: 457
Likes: 0
From: Burleson,Tx
Considering the purchase price of the parts, and the time and labor to install all a this, are you really saving money on fuel?
No. Actually YES I do save alot.
Consider how much gasoline one could buy for the 1000's of dollars spent for this swap.
Here in SoCal, diesel costs more than 91 octane premium gasoline. The average price for diesel is $5.07 a gallon. Avg diesel price here has been $3.85 per gallon You can do the math at 12-14 mpgs for an old school gasser or 32 (and thats mostly city) for a small diesel. Regular unleaded about 3.55 per gallon.
Last time I filled up, premium was $3.97 a gallon. Regular was $3.57 a gallon.
No. Actually YES I do save alot.
Consider how much gasoline one could buy for the 1000's of dollars spent for this swap.
Here in SoCal, diesel costs more than 91 octane premium gasoline. The average price for diesel is $5.07 a gallon. Avg diesel price here has been $3.85 per gallon You can do the math at 12-14 mpgs for an old school gasser or 32 (and thats mostly city) for a small diesel. Regular unleaded about 3.55 per gallon.
Last time I filled up, premium was $3.97 a gallon. Regular was $3.57 a gallon.
CC22, You're spouting some awful big numbers there. Please share with us, what one should expect to spend (in real time) to add a setup like yours to his existing ride.
I built my whole truck in a 5 month time period working on it when I was home from buisness trips and in that time period I really took almost 2 whole months off, the rest of it I didnt work on it everyday I could have. I also swapped in a crown vic front suspension, installed a new crown vic rear axle, 03 ranger fuel tank and many other custom touches so really I know for a fact you could install the little diesel engine in about a weeks time. I also paid $2k for the diesel rebuilt, $550 for the overdrive trans rebuilt, $600 for the engine to trans adapter, and had the scrap steel around to build the mounts, $150 for new steel driveshaft, $150 limited slip 8.8 rear axle.
Oh yeah lets not forget it will run on vegi oil at about 10 cents a gallon ( you have to figure in your filter costs) so that blows most any gas motor out of the water for fuel costs.
John
I built my whole truck in a 5 month time period working on it when I was home from buisness trips and in that time period I really took almost 2 whole months off, the rest of it I didnt work on it everyday I could have. I also swapped in a crown vic front suspension, installed a new crown vic rear axle, 03 ranger fuel tank and many other custom touches so really I know for a fact you could install the little diesel engine in about a weeks time. I also paid $2k for the diesel rebuilt, $550 for the overdrive trans rebuilt, $600 for the engine to trans adapter, and had the scrap steel around to build the mounts, $150 for new steel driveshaft, $150 limited slip 8.8 rear axle.
Oh yeah lets not forget it will run on vegi oil at about 10 cents a gallon ( you have to figure in your filter costs) so that blows most any gas motor out of the water for fuel costs.
John
I love my conversion and while its not the cheapest way to save fuel I felt it was best for my needs and wants. I get to drive a cool old truck and get to stay away from the little wind me up cars that I cant stand. I also get to drive around with the power of a diesel which is great, and for all the tree huggers out there I can run on vegi oil so I am doing my part for the environment. Another reason I chose my conversion besides mpgs is that it rides like a car due to the 07 crown vic front suspension and I can save myself about $13,000 a year in fuel (That is figuring diesel at 3.80 per gallon.)if I use vegi oil when cruising on the highway. When you take that into account and the fact that my company pays me mileage then I am actually making money on my conversion.
Arent diesels awsome! Randy
getting 32.4 mpgs in my little diesel F100
