V-6 in '08 Wrangler???

Yup, it would appear you now have a mini van engine. No more crawling up the sides of sand pits or over rocks at 400-500 rpm like the old 6 would do. You now need tire spinning, hole digging, rpm to get anyplace.

Probably better on the highway.

Mike

Jack Carter wrote:

Maybe you should check out the gear ratios in the 6-speed transmission and then take one for a test drive - preferably one with the optional 3.73 axles. If you're open minded - as opposed to empty headed - you might change your mind!

JP Magazine published a torque and HP curve chart from an independent dyno test showing both the 4.0 and the new 3.8. The curves are just about exactly the same util up high in RPM, then the 3.8 has a bit more torque and hp. I have also read that it takes about 5000 miles to break into this level of performance so in test drives of new vehicles the engine tends to feel sluggish.

Actually, on paper, the torque curve of the 4.0 is crappy compared to the 258 and even the old L and F head engines in terms of peak torque RPM. However, in practice, jeepers love the 4.0.

since you already own the vehicle, why worry about it? Especially if you just bought it with the lifetime warranty.

I have not seen the dyno results you say, maybe if you could post a link. But I have to note, that usually dyno results range from around 2000 rpm and up. They don't tell you what is going on bellow 2000 rpm, and most of the driving is in the 1200 - 2500 rpm range.

Bill Spiliotopoulos, '96 XJ, '06 TJ.

Mike is right. There is no substitute for a low-revving, high torque engine with high rotational mass. Simple physics says Mike is right and you are easily persuaded by marketing smoke and mirrors.

Cheers,

Earle

Some of my facts were off due to bad memory but here is the link to the chart. It actually goes to low RPMs.

You feel the need to insult my opinion just because you got took and didn't look under the hood?

I feel sorry for you, but Chrysler 'did' make that special oil additive 'just' for the Mitsubishi smokers so it might last a little while... ;-)

So I have the sand pit wall in mind if you want a test, bring on the mini van engines!!!

Seriously, it would be fun. I am in the Toronto Canada area and love to sit at the top taking photos of folks trying to make it.

I'll even post the photo album up.

Mike

Jack Carter wrote:

six?

It could be lying but supposedly it is a chart that is not generally made available to the public. Who knows? What I can say is that some local guys who had Yjs and TJs and then bought JKs are pretty happy with them. A shootout was organized locally to test the TJ rubicon and the JK rubicon on the same day, same obstacles, etc and the JK was declared to be the clear winner. Another shootout was organized to compare the TJ rubicon with a Toyota FJ cruiser and the cruiser had to abort because the control arms were getting bent just from the flexing!

What total garbage -- particularly in light of the chart NRS was so kind to link. The preceding posts make it sound like comparing this "minivan" motor to the I-6 is akin to comparing a wicked, ill-tempered race motor and its street counterpart. So we've lost a bit of rotational inertia from the engine -- I'd put my money on a good driver any day over the _grand_ difference between these two powerplants. ...garage equivalent of armchair semantics...so let's talk about that really butch 4.0/4.2 .... is it more "Jeep", or is it, too, a grocery getter - just from AMC?

Anybody care to comment on the huge flywheel effect or massive torque rise on a stock-engined a Samurai? Must make for a lousy crawler....

Jon

Cool. Let us know the real outcome. Not what a bought and paid for magazine would print. God Bless America, Bill O|||||||O mailto: snipped-for-privacy@aol.com

Sucker. But the fifty pound flywheel like used on the Buick V6 to allow it to idle did have a secondary advantage of storing inertia energy. Your V6 won't have it as also eats gasoline. But you may buy them for the wimpy four bangers. And of course we all know of the go quick small block, thirteen pound wheel, and it's rough idle. God Bless America, Bill O|||||||O mailto: snipped-for-privacy@aol.com

Part of the consideration to this conversation should probably be made to the weight of the vehicles as well. The Unlimited JK weighs a full 1000 lbs more than my YJ. The weight difference in the two I'm sure is what really gave the JK a sluggish feel when I drove it and not so much even the V6. I'm willing to bet that the 3.8V6 can do just as well offroad as the 2.5L4 has been doing for people in their Jeeps.

I'm not the least bit "worried" about it - just curious. I've owned six Wranglers, starting with a CJ5. And I liked all of 'em. The one I traded in on the new one was an '03 Sport. And it was a terrific performer. But I like the '08 far better than any of them - off or on road, but admitedly especially on road. With the six-speed transmission and a really down-in-the-basement 1st and 2nd gears, it's a ball to drive anywhere. And the torque and horsepower curves seem to sum up everything very well.

Here is the link. It is in Spanish so not everyone here will understand but the general consensus was that the JK did a bit better. You will see from the pictures that it was tough terrain and the vehicles were used hard.

My '08 X weighs 310 pounds more than the '03 Sport I traded in.

yes it's a mini-van motor but it isn't produced by Mitsu - in fact Chrysler has run a Mitsu motor in more than a few years (the last i remember was in the Sebring two generations past).

this is a 60 degree cast iron block push rod motor and while it is more free revving and has a higher red line than the 4.0, it is tuned for low rpm torque. mini-van moms appreciate the same driving characteristics that jeepers do ... torquey off the line, smooth idle, good tip in response, not peaky or pipey torque and hp curves.

a good source or information on JKs is found on Allpar.com