TJ engine swap - 4.0 to something with better MPG?

Harris, it's an election year, civility goes out the window...

;-)

There's room for improvement. Here's a pretty direct comparison between a Wrangler SE and the Honda CR-V.

Wrangler SE: Curb weight 3235, 147 HP @ 5200 RPM, 165 lb-ft @ 4000 RPM, EPA city 18, highway 20-21.

CR-V: Curb weight 3258, 160 HP @ 6000 RPM, 162 lb-ft @ 3600 RPM, EPA city

The Honda makes more horsepower and the same torque (at lower RPM), but gets

-John

Generic did pass the time by typing:

It's all in the transmission and in driveline losses with conribution from more efficient engine tech.

Even the ZJ got a good boost in power and economy by introducing a hemholts tuned intake rail rather than the straight shot like mine has. Heck, I'd like to have the newer generation 5 speed tranny. Too bad it's not compatible with the ECU. Stupid pooters. :)

That and the CR-V is more "aero" than the Wrangler. Not like I fly the most aerodynamic brick either. :)

Generic proclaimed:

But why not? Just swap in the displacement on demand Hemi and get both power and mileage. Or find a VW TDI V-10 diesel and drop that in there...

Please tell me there is a God & he will look down upon us on that day.....

Man I must be lucky cause I get about 16-18 around town with 31's and 2" lift on a 04 TJ 6 Cyl auto!

What does that have to do with anything?

Some Jeep setups get 10 mpg. Some Jeep setups get 15 mpg. Some Jeep setups get 20 mpg.

What could happen with more modern engines? Some Jeeps may get 25 mpg and have the same power. All the setups may improve.

-John

i pulled a CRV off the silverlake sand dunes this weekend with my 2000 tj, getting about 17 miles to the gallon the whole time. lmao

First off, the SE is a 4 cylinder engine and this discussion was related to the 4.0L six cylinder (tractor) engine we all know and love.

Secondly, 3 mpg difference is not that much. Especially considering the Jeep running gear will allow you to actually go *off-road* and the Honda running gear is designed for cruising the local mall. With that in mind, the 3 mpg advantage of the Honda does not seem big enough to me...

-Fred W

Well, yeah... You can do a similar exercise by comparing the Ford Escape 6 cyl to the Jeep 6 cyl.

Again, yeah... 3 MPG is better than 10%, 5 MPG is close to 25%. The vehicles are obviously meant for different purposes--but the CR-V and Escape get better on-road mileage with the baggage of full-time 4wd.

What is WRONG about selling them with newer engines? Especially if you can get more power and better mileage at the same time.

-John

It's not wrong really, but there's a lot to consider when actually comparing the vehicles side by side (even if you stick with the 4cyl SE vs. say the 4cyl CR-V). For starters, the stock SE comes with P215/75R15 tires along with a 4.11 gearing. CR-V comes with P205/70R15 tires, and I can't find *any* info on gearing.

Now leaving the gearing aspect out of the equation (although I would pretty much assume that the CR-V is geared for street use, not off-road), you're comparing mileage of a Jeep with ~27.7" tires vs. a CR-V pushing ~26.3's. That right there would probably account for the 'superior' CR-V mileage. If not, give the CR-V a tranny and gearing actually suitable for off-road use, and I think you'll for sure see its mileage spec drop, perhaps even lower than that of the 4cyl stock Jeep.

Newer quite often isn't better. :) 'Specially as hard as it is to work on those damn foreign engines that are designed to be completely dis-assembled just to change the oil filter (exaggerating of course ) hehehe. Oh, and the Jeep has the higher max torque, at only 400 RPM's more than the CR-V. Can't find the actual curve, but I bet the Jeep still has more torque than the CR-V at practical off-road RPM's in 4WD-Lo.

Dave

One gets the feeling here that some Jeep fans wish it were still, say,

RJ did pass the time by typing:

:) That only is till the ol carb is sitting at too great an angle and the engine is sputtering on fumes. Then fuel injection becomes the next killer mod.