MPG improvements on a Ford 400

[LEB Ben]

Since there seems to always be someone asking how to improve mileage in 73-79 trucks, I figured this info could be useful to someone. I started with a 1979 Bronco with a 1978 400 that had roughly 100k original miles. I was getting somewhere between 7.5-8mpgs with an engine that was a little tired and was leaking. After 3 tanks of gas, I am right at 9.5mpg's and that's with some relative flogging, burnouts and excessive idling. I also bumped the timing from 12* to 14*. So once I tone down the lead foot, my numbers may increase. Anyway, here's a part list of everything I used to increase 1.5-2 mpgs:


Timing Chain: Feels a little cheap, so I think I'll go back to Cloyes next time around
http://www.summitracing.com/parts/CCA-2121/


Gasket Set: Used every piece in this set except for the valve stems, personally I prefer cork gaskets, but the rubber components seem to be doing the job

http://www.summitracing.com/parts/FEL-KS2308/


Coil: Figured the upgrade was worth $30:
http://www.summitracing.com/parts/PNX-40011/


Plug Wires: I prefer the straight plug boots, and probably will never get 135* boots again. Seems like a good quality discount set of wires to upgrade to.
http://www.summitracing.com/parts/TAY-64663/

Carb Renew kit: I was surprised at how good my carb looked. I coulda reused everything, but figured while it was apart and I had a kit, it wouldn't hurt.
http://www.summitracing.com/parts/HLY-37-935/


Spark Plugs: Regular old copper Motorcrafts, no need for anything else on street rig.
http://www.summitracing.com/parts/ACF-SP450/


I also replaced all filters and got them from local parts stores. I used Rotella T 15w-40 from Wal-Mart and NAPA 50/50 coolant, whatever was on sale.



Disclaimer...results may vary, just figured I'd post up what a couple hundred bucks and a good tune up could do for your ride.

While a couple hundred may sound like alot to spend on this stuff, I figure I can roughly go another 50 miles on a 25 gallon tank. 50 miles used to be 7 gallons of gas. At 2.80 a gallon I'm saving $19.60 to go the same distance as before. So after fill up #10, I should break even. I fill up twice a week, so in week 6 I'll be money ahead.

[Truckin4life]

winnah winnah chicken dinnah!

[gsxr1238]

That is a significant increase.Good job!

[LEB Ben]

Originally Posted by Truckin4life

winnah winnah chicken dinnah!

Thank you thank you. I just figured there's always someone hopping on here wondering how to get their brick hybrid type mpg's. Well this is about as good as you're gonna get. Figured a 25% increase was pretty good and it might show what you'll have to do and go through to get it. I could do a write up, but the majority of it is self explanatory and I already did a timing chain write-up, and that's the bulk of the work.

Originally Posted by gsxr1238

That is a significant increase.Good job!

Yeah...I thought so. I'm excited to see what my highway miles are gonna be like. I used to get 10, I'm hoping for 13-14. And I'll be able to figure it up this weekend.

[nobodyspecial]

best way to greatly increase mileage in our trucks:

[LEB Ben]

I agree 100%. If you want good gas mileage, get a car. But...since it seems to be asked quite often, I figured I'd post up how to maximize mpg's for these rigs. And figured it might be helpful to someone to see what a realistic number might be. Sure, there are some variables like 2wd vs. 4wd and auto vs. manual and there may be better products out there, but this is a good starting point.

[hollenjoe]

well theeres always expensive ways of getting better mpgs, compression, better engine components, Im currently preparing an aod swapp for my 408, its pretty easy now but still a bit expensive ( about 1500 bucks if you do the job yourself) but will increase significantly my mpg, theres tons of ways of having a powerfull yet no sooo expensive to drive plant...

[LEB Ben]

Originally Posted by hollenjoe

well theeres always expensive ways of getting better mpgs, compression, better engine components, Im currently preparing an aod swapp for my 408, its pretty easy now but still a bit expensive ( about 1500 bucks if you do the job yourself) but will increase significantly my mpg, theres tons of ways of having a powerfull yet no sooo expensive to drive plant...

Very true...but most of the things on my list are things anybody with a pulse can do. Not saying there aren't other ways to go about getting mpg's, just thought these were the easiest and took right around 10 hours to do from start to finish. That being said, I have no clue which of these things made the biggest improvement or if they all contributed equally, but it's something everyone can and should do.

[nobodyspecial]

I just feel that if you build a big truck with a big engine, MPGs are not something you worry about with it. If you have the money to build it, you have the money to fill it. Of course, you want it running efficiently and not be out of tune, but chasing that last .5 MPGs seems like an exercise in futility to me.

[LEB Ben]

Sure is...I wasn't doing this to chase down any mpg's, I knew it was gonna be terrible regardless. I was doing this stuff cuz it needed to be done. That being said, I was pleasantly surprised when I saw a 2mpg increase 3 consecutive tanks. So I figured I'd share the results for those that want their 6000lb V8 rig to get hybrid mpg's. And even with all that work...I still only got an increase of 2mpg's. There is no miracle bolt on that get you from 10mpgs to 20+mpg's. You have a truck with the aerodynamics of a brick, you bought it because it was tough, cool and cheap.