Gas Mileage Thread

[j0114]

I know this is something that can help us all, who drive these on the highway. Mine varies If im on highway and I can keep it in 5th gear Ive gotten 17 on an all highway flat surface,
Around town I think i was getting 12.
But As an all around which I drive some downtown and I do a 60 mile 1 way to go see family sometimes so I was aver around 12-15 depending.
Which I thought was pretty good,
One thing I may should point out was most of my jeep is new it was just finished in a restore, so I am assuming the crate motor , Transmission etc having the new parts helps me with the mileage, I honestly would like to gear it a bit lower with the 33's but im worried it would kill the mpg's i get not, id sacrifice some but i dont want it to go down to 8 mpg.


Anyways I am new to the CJ7 world or a better answer would be I am just getting back into it, I have had lots of jeeps and I wanted what I got or a scrambler and the quality scrambler I was looking into was a bit more than I wanted to spend and when I found this triple back 86 I could not pass it up,
I specifically wanted an 85 or 6.

Anyways. enough about me and my 7 lets talk about what you guys are doing to help with the fuel economy.

Does the fuel injection systems help - i got another post hoping to go into that in detail on the fi systems, It is an expensive option but i was going to list it.

What about a new or better ignition system,
Ive heard things about an Performance Distributor and iginition kit helping out with fuel economy also,

I know keeping your tires rotated and properly inflated does make a difference also,

Or ive heard good things about the MSD ignition package,

alot or most of these things I have not tried but just read about on forms doing research but I felt together we could debunk alot of these or rate/review them.

I would also love to hear what any of you my fellow jeep enthusiasts are doing to help with fuel economy. I hate using my restored 7 as a daily driver but I am not going to have a choice for a 2-4 month period max, could just be 1 month, but even if I am not driving daily I would like to get my mpg up.

As a side note, Ive seem to have best result with 89 octane, also there are a few stations fairly close to my house that does not use ethanol, I have not had any ill effects when I have to get some of the gas with ethanol but when I fill up at the old school gas station without the ethanol I get better gas mileage, not in my head I got a small notebook and keep up with it, but its also I hit a more hilly area or got on the interstate more or did something different with the ethanol gas i didnt realize to hurt its numbers, but ive never not gotten at least 1.5 mpg better with non ethanol, one time i got 3.65 extra per gallon.

I know i got a little long winded but I think this could help alot of us

thx

 

[CJ]

Hello j0114 and :ww: to our site. Can you fill out your profile with your CJ info so we know what type of CJ, engine, diffs, gears and Transmission you have? That will allow others to compare vehicles (among other things).

 

[gillmore]

I try to buy the best quality stock parts and keep things well tuned and maintained. I get about the same MPG as you do although I haven't been diligent on keeping records. I also installed a vacuum gauge, which can visually remind me that I'm being too aggressive on the throttle when it isn't necessary. It can also indicate other problems in addition to vacuum leaks. See How to Use and Interpret a Vacuum Gauge

 

[gert]

Well you can start with the usual hot rod stuff.....an engine is an air pump the more it can get in and out the better it performs ssooo an unrestricked as possible intake/carb/air cleaner as possible and header/cat/exhaust pipe will get you started.. A hot ignition(HEI/MSD) electric radiator fan all this adds horse power and frees up torque which makes the engine work less/ use less gas.. Fuel injection helps as it is more percise I am going with either the Howell set up or the junkyard GM set up (new versus used).... jo114 I like your vacaum diagram very informative

 

[Sasquach]

To get accurate milage figures you need vehicles with accurate speedos for a start and concidering most CJ's do not have stock size tires or in some cases even working speedos you can not get quality data for any kind of comparison.
In responce to your question about FI I can say my experience with going from a 1bbl to Mopar MPI seems to have doubled my range but is not backed up with hard numbers but of how often I am visiting the gas station. Cost effective? probably not but I would not go back.

 

[BusaDave9]

To get good gas mileage make sure you engine is tuned up. Air filter replaced. Tires at the correct pressure. Cat isn't clogged.
After that comes trying to improve on the gas mileage of your jeep from what the factory intended. Yes fuel injection can meter the fuel better and give better mileage.
A good ignition system such as HEI can almost always help an AMC 6 or V8 or ... What do you have?
But when it comes to imporving on the mileage that the factory built into the engine it's hard to get your money back. A good HEI ignition can cost $200 to $400. A fuel injection system can cost thousands. It is good to spend money to save gas and the environment but it is hard to come out ahead. Even spending more on high octane usually doesn't pay off.
Do as I do: I use my old CJ (with a V8) only for off-road and I use a motorcycle or small car for a daily driver.
Just my 2¢

 

[giantsfan]

To get good gas mileage make sure you engine is tuned up. Air filter replaced. Tires at the correct pressure. Cat isn't clogged.
After that comes trying to improve on the gas mileage of your jeep from what the factory intended. Yes fuel injection can meter the fuel better and give better mileage.
A good ignition system such as HEI can almost always help an AMC 6 or V8 or ... What do you have?
But when it comes to imporving on the mileage that the factory built into the engine it's hard to get your money back. A good HEI ignition can cost $200 to $400. A fuel injection system can cost thousands. It is good to spend money to save gas and the environment but it is hard to come out ahead. Even spending more on high octane usually doesn't pay off.
Do as I do: I use my old CJ (with a V8) only for off-road and I use a motorcycle or small car for a daily driver.
Just my 2¢

i agree holeheartedly, i do the same thing