Squeezing MPG's out of a Jeep - or atleast trying.

[MetroMPG]

Originally Posted by RoboMike

Other than that, I fail to see why you keep replying for an argument - do you not have anything else better to do?

Guys, a reminder to please try to stay civil. Thanks.

[elhigh]

Bud, you're going to want to put those doors back on. Sure they provide a "wetted surface" that produces more skin drag, but removing them introduces a huge amount of turbulence that wasn't there - and is way worse than the skin drag you eliminate.

Seeing your statement regarding the trails and planning (?!) on future rollovers, I won't recommend removing your rollbars unless you want to take the expensive step of having new ones made that will permit you to fab a hard top that tapers toward the rear. You'd still have your roll protection, but it would frame a compartment that had more contour and less boxiness.

Also seeing the trail statement, I won't recommend you try to lower your ride. Too bad, it would help. But a front airdam that could be quickly and easily removed would go a long way toward smoothing out the airflow under your ride. We all know that Wranglers aren't built so much with an eye toward pretty as they are toward functional. I daresay the dirty side of your car is easy to work on unless you've add skidplates, and provides lots of ledges and crannies for the wind to catch on. An air dam gets that over the car and off to the sides; if it's easy to remove and replace, you're more likely to keep using it.

Side skirts help. Again, removable for on the trail.

What's up with the idling fuel usage? That can't be right. Maybe there's something wonky with your electrics that at low revs your fuel gauge isn't getting enough juice to read correctly? I've never seen that before, and that's with experience in two different generations of Wranglers and God knows how many other cars and trucks, including one I had sitting in the snow for two hours idling. Fuel needle didn't even move that day.

Good luck, man. My mom drives a Wrangler; if you have good results I may have to kidnap her car and do some surgery on it.

[nascarnation]

Originally Posted by RoboMike

Oh Reformed ; my jeep is an I-6 (straight 6cyl) - not a V-6 (they don't make those for Jeeps; less torque).

actually all the current Jeeps that aren't V8s are
V6s.
http://www.jeep.com/en/2008/wrangler...ility/engines/

http://www.jeep.com/en/2008/liberty/capability/engine/

[Red]

meh we can all agree that our respective junks all slurp gas like no tomorrow. Be it at idle or under load. Another thing we all know is that the gas gauge is crap when it comes to accuracy. Assuming that it still works. I would say its not worth making any claims based off the gauge.

According to my scan gauge:
At idle, the 4.0 does consume around 0.6-0.7 GPH, @65MPH around 3-3.5 GPH

But if you are sitting at idle with the AC on, yeah it does look like the gas needle is attempting suicide. Idle flow rate remains the same. Done it enough time when waiting certain people The gauge just sucks.

Adam's TJ is a 3spd auto. Its FE pretty much sucks. The numbers you posted were for the 5psd. The auto has an average 15MPG combined.

Everyone is pretty much right, by his own perspective and instrumentation.

Chill dudes.......


nascarnation,
The 3.8 isn't a real engine. Only the 4.0

[elhigh]

Originally Posted by nascarnation

actually all the current Jeeps that aren't V8s are
V6s.

And the worse for it. Those old straight sixes were the bulletproof bomb.

[adam728]

Sorry for coming off as a dink, I guess we agree to disagree.

As for airdams and such, I've wondered why front skids haven't caught on with Wranglers. There are a few for XJ's, and I have an older Land Rover magazine from Europe, it seems every rig in there has a tie rod skid that would double as an airdam.

Tomken does make a small one for the TJ's, one guy on a Jeep forum claimed a slight increase in gas mileage, although I don't remember him quantifying it.
http://www.tomken.com/detail.php?id=107

A nice custom made one

I like it, but am afraid out here wheeling rocks I'd get hung up and rip the dang thing off trying to back out.

And I haven't head much about it, but at one time a few years back a manufacturer built a TJ with the front of the hood dropped something like 3" for better visability. There was talk about a kit to lower the radiator support/grill and throwing on this custom hood, but I've never heard anything since. That would help aerodynamics some.

For the most part I accept that I drive a brick, and therefor don't drive it very much (just for fun really). In fact, my last fill up in the garage here is shown from over 2 months ago, and that really was the last time I filled up the Jeep. Aero mods or not, I drive a brick with drivetrain that was standard 40 years ago.

[Red]

Most of the hype nowadays is rock crawling. Most go or shoot for crossover steering anyway. They'd look at a tie rod skid as something easily smashed.

[johnpr]

Originally Posted by Red

nascarnation,
The 3.8 isn't a real engine. Only the 4.0

hey now! i can out tow any of the other wranglers!! seriously though the 3.8 does have great power, i have been offroad a numerous amount of times with it and towed everything from small cars to pickups and also an old 70's 36 foot winnebago!

anyhow on to the focus of this thread, i coast to stop lights with the engine off, it kills the ease of steering but is worth it, also i never go above 55.

slanting back the window has many logistics issues, first moving the top towards the rear means redesigning the door, moving the bottom forward means figuring out the windshield wipers.

here are a few of the ideas i had for my '02
http://ecomodder.com/forum/showthrea...deas-1517.html

and this is my current project (my '07)
http://ecomodder.com/forum/showthrea...mods-3035.html

an easy mirror solution is getting some smaller mirrors from autozone (or similar retailer) and replace the stock ones, i know the mirrors on the older jeeps where not as bad as the '07 though so maybe not much of an issue for you.

also there was a good point about the tops, a worn out top will be bad on fe but a good soft top is just as good as a hard top for the following reason

Originally Posted by DifferentPointofView

Jeeps have such a high windshield angle, that the air doesn't re-attach to the roof of your jeep, and just whooshes upward into the sky, as you can tell during the rain .

i hope this helps in your quest

[Red]

Just messing with you JK guys.

Wonder if instead of a drastic body change, some kind of large transparent bug shield that would let you bypass the windshield?

[johnpr]

that is what i have been pondering, but on my JK the windshield is slanted more and the edges are rounded a bit better so ive been wondering if that helps much