2007 Wrangler???

It sounds terrific to me. And don't count out the V-6 unitl you try it. It has MORE TORQUE and horsepower than the old, inefficient AMC I-6 which has seen better days. (I'm running for cover now!!!)

Only time will tell the I-6 is pretty much bullet proof and many have 200k or more with out any rebuilds. I am just glad I got mine.

It might be old, but it's tried and true and has never let me down.

Carl

It has it's good points... it's tough... it's got lots of low end torque... actually that's it... 2 good points :)

I think you could give it a plus for having a decent selection of aftermarket parts.... One Aluminum 4.0 conversion head, basically 2 "performance" intakes (Offy and Clifford)... a handfull of headers... a couple home brew ignition mods (HEI and TFI) and a few aftermarkets like MSD... and there's a few stroker options. A couple Carbs and a huge selection of fuel injection kits. There are no block options, although Hesco was talking about an Aluminum 4.0 block for a little while... it seems to be dead in the water.

The bad points are; it's heavy, it's HUGE relative to it's output... For it's displacment many modern engines have more than triple the HP and Torque output. It's a gas sucker even ignoring the Jeeps aerodynamic faults, it has an almost absurdly small useable RPM range.

It's basically twice the size, and 150 pounds heavier than anything else putting out 100-ish rear wheel HP. Couple that with the Jeep and you have an engine that often strugles to go up hills at highway speed once it gets a bit tired or out of tune.

All that said, it does have a certain character to it, but when I find the right excuse it's gone from my 88 YJ. Maybe a 5.0 or 4.7 Mustang engine (lots of aftermarket, wont be the first one to do the swap) or maybe a CRD from the Libby (hopfully someone else will have done one by the time I need to).

If you want to buy me one, there is a place in Denver I can take it to get dyno'ed. ;^)

Earle

Does anybody here have a website address that has a "torque curve" chart for the I-6?

Tom

snip

is it the same 3.8 that has been in the minivan? Here's a link to atorque curve from the 2002 3.8 I found:

Chad

04 LJ 3" BDS 33's etc...

Yep, my wife's 04 WJ was the last year for the I-6 too and she bought it becaues of the I-6, Tried and True. Coasty

I don't have a link but I do have a copy of the 4.0L I-6 torque curve and it shows 210 ft-lbs. at just 1200 RPMs all the way up to nearly

5,000 RPMs. It's pretty flat between 1200 RPMs to just under 5000 RPMs and it's all above 210 ft-lbs at all RPMs between them.

If you look at that 3.8 chart, you'll see what I mean about the V6 not developing that kind of torque until around 2300 or so RPMs and it's a very "peaky" curve, not even close to the relative flat torque curve of the 4.0L. Below that RPM, the V6's chart shows the torque takes a nose-dive. This is why the 4.0L is such a superb engine for offroading, it's flat torque curve that starts at just above idle RPM. Too bad the government made it difficult enough that Jeep had to drop the ideal offroading engine in favor of one with less than ideal torque characteristics that are way less suitable for offroading.

What I don't understand is how GM could develop a new inline-six that has good low-end torque and Jeep can't. I could probabl learn to live with that new V6 if I were to buy a new 2007 (which I have no plans to buy) but I wouldn't like it. :)

Jerry

snipped-for-privacy@gmail.com wrote:

Not a good pic, I'm afraid, but enough to prove your point.

Dave Milne, Scotland

A change in camshafts can DRASTICALLY change the torque curve of ANY engine.

The website seems to indicate that it has a wider stance and longer wheelbase than its predecessor. Anyone know how much in each direction?

The track ("stance") is 3 1/2" wider (!), and the wheelbase is 2" longer.

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I suspect he's trying to hint that swaping out a Cam can make other engines -- which may be much more desirable all around; low torquers.

At least *I think* that's what he's getting at :)

Just off the top of my head, the I6 has a longer stroke and greater rotating mass, which makes it "torquey". You can't duplicate that by swapping in a cam.

Earle