GO DEVIL, you drink too much gas!!

Guys,, I recently picked up another flat head GD powered flatty to use whilst the other one gets built, AS YOU DO!!!.

Still have some work to do on this latest addition before it hits the road, but I just read someplace that those old 2200cc motors are only good for around 13.8 MPG , this is my first ever Jeep with the flat head motor fitted, so does this MPG sound about right to you fellas?? I thought it would be good for at least 18 mpg.

Either way I shall live with it, as I just love those old motors, but if there is a way of improving the MPG, Im all ears.


MPG has never been a big issue with me in the past, but Gas prices here in UK are around $10 per gallon at the moment thats without the lead additive at £9 ($18) a can

Our government said ''we have to go green'' so I gets this Gosh Darn olive drab flatty, and now they just screw me for more What does one have to do to please these greedy people:?

 

Hows the prices of propane over there?

 

PHEWWWWWW........

For a minute there I thought this was some sort of group intervention.. I was expecting the door to get kicked in and be drug off to alcohol rehab!

My little Flathead works HARD all the time. It takes lots of gas pedeal to get up to speed and my foot is on the floor for anything over 45 mph. I would think a gear change and an overdrive would vastly help the economy. These are good dependable little motors,the trouble is they were not designed to keep up with modern roadspeeds.
Donnie

 

The WWII engines were tested by the Government back in '41 and recieved a 20 mpg. (not that then, as now these are even close) Plus the axles were geared at 4.77 for military and the cici jeeps were 5.38.
If your looking for gas mileage, you will never find it in any Jeep, even today.

 

I know the flatheads are not renowned for good gas mileage, but 13 mpg seemed a little low to me, 20 mpg average is around what I thought, its a CJ not military :driving:




Did my thread sound a little grumpy then?

 

Propane is not too bad £ here YET, but about 80% of our pump (petrol) gas prices is for tax, so Im guessing its only a matter of time.

Interesting thought though, many newer Jeeps here run on propane.

And many of the diesels here are turning to veg oil, or a 50 x 50% mix.

 

Jeep Compass R)R)

You could convert the Lhead to propane, or find a small 1bbl TBI unit and try to fuel inject it. Someone here was doing it or had done it, I just don't remember who.

 

for the 1000 KM it gets driven per summer, its not worth messing with to convert to anything.

 

letsee here, 1000 miles times, no, 1000 KM, (sheesh) times 3280.83 equals 3,280,830 miles....

no, no, no, That for feet...

Lemee try again,
1000 KM times 0.62 equals only 620 miles...

hardly worth it. Enjoy it like it is. Any money thrown into her to make her more efficient is gonna take a bit to pay off....

time for a

 

Jeeping is a hobby...Well lets just say that older, less "green" Jeeps didn't ever deliver on the MPG. I have talked with owners today of the Jeep products and find that they aren't saying the Jeep is a shining example of gas mileage.
For an old Jeep you run around in in the summer or to the store whenever it's just a price that is paid to have everyone that see's your Jeep wave and oogle. THAT's worth a couple dollars a week.

 

If you want Green just paint it Olive Drab.

 

fixed that for you. Dosent deserve to even have the "J" word in the same post.

As for the fuel mileage (or kilometerage for you metrics ) 99% of the things that you will do will never pay for themselves in fuel savings. But i've heard that a good upgrade for better power and possible mileage would be to go to a pertronix ignitor in the distrubitor. They are relatively cheap, and i've heard good thins about them. The only reason I havent installed one is that the points and condensor were cheaper at tune up time.

 

For the $10 / gal their fuel costs... I would put a propane kit on in a second. It is a lot more common to have a propane vehicle over there too. so filling wouldn't be an issue. A kit from an old forklift would be pretty cheap too.

 

I went from 12.5mpg to 16.5mpg with the Overdrive. might be worth looking into as well.

Do you have locking hubs? you'll pick up a couple mpg with them.

switching to syth oil helps too, would use it in the diffs, everything else leaks too much.

I have noticed I pick up 2mpg running with the windsheild down (weather permiting of course).





and should be 4.88, NOT 4.77 in the axles.

 

Thanks for the tips fellas, seems close to 20 mph could be had with a little work, this cj3a has locking hubs & 750 tires.


Thinking out loud here -
Years ago I had an old Ferguson TE 20 tractor that run fine on TVO, it used to start up on (petrol) gas, then switch over to TVO when warm, something to think about for the Jeep maybe if our gas keeps going up

Either way the ol CJ is here to stay no matter how much she drinks:driving:

 

The old CJ's really weren't built to run at any thing over 50 mph.
The 5.38's were installed so you could go where ever you wanted, just not very fast.

I get 17 mpg from my F134 with the 5.38's, but I don't run her over 50 mph, and usually at 45 mph (which is the posted speed limit on the old hiway that runs from Florence, AZ to Phoenix,AZ.) Any one that wants that 150 dollar ticket for speeding can just go around. I leave the house early enough so that I don't have to speed to make up time. Plus the closer to Phoenix, the better the chances are that your top speed will be something along the order of 3-5 mph, anyway.


Just changing the gearing in the differentials from 5.38 to 4.10 or 4.11 (forget which is available) will improve your fuel economy and your top speed, while still giving you a pretty fair crawl ratio for that off into the wilderness stuff we all like to do.