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Unread 12-20-2011, 04:59 PM   #91
Mictrik
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Quote:
Originally Posted by Fellows View Post
I totally agree with the exception of the current Chrysler not having a hemispherical design. When this engine came back out, there were countless cutaway models at carshows and in magazine's showing the hemispherical looking head. I'm not sure if its exactly the same dimensions as the originals, but it definately had the valve on each side requirement along with the giant, overweight looking head.
It is not a true hemispherical cylinder more of a triangular head. Little advantage to it, other than gimmick and using their "Hemi" trademark in my opinion. Multi-valve heads & oblong or other shaped heads designed to cause currents in the chamber to better mix the fuel into a combustible gas have really made the hemispherical chamber especially in its two valve incarnation, obsolete. My bet is that Chryslers present design uses two spark plugs as a way of keeping a somewhat kind of hemispherical head while reducing hydrocarbon emissions. A feat better accomplished with 4 valves head shaped to further facilitate atomization. You see they trade marked that name "Hemi" and they want the most out of it. The HEMI design even when it had more merit was never a great choice for the Wrangler. The design requires way too much engine bay space due to the need for thick convex shape outside cylinder heads and the more complex valve linking to accommodate the odd valve stem angles. The design is wasteful in terms of fuel, and large relative to power output; two things we do not need in an off road vehicle. An off road power-plant should be efficient, simple, and reliable; for me this means a Diesel...

In a race engine that produces its peak torque & HP at relatively high RPM and before 4 valve heads & other performance efficiency methods were commonly applied, the cross flow ability of the hemispherical design provided more value. So in certain applications, given certain constraints the design has merit but just not for Wrangler. That is unless the driver just likes the trademark "HEMI" stamped on their Jeep.

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Unread 12-20-2011, 06:09 PM   #92
OutlawJK
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Could you imagine having to listen to that rattling diesel engine all day !!

I own a Dodge with the cummins engine and love it
It's a 2500 4wd and it gets great mileage

But I like the 3.6 in my jeep with the top off
Not having to hear the constant rattle
And smell the fumes of a diesel
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Unread 12-21-2011, 12:52 AM   #93
Mictrik
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Quote:
Originally Posted by OutlawJK View Post
Could you imagine having to listen to that rattling diesel engine all day !!

I own a Dodge with the cummins engine and love it
It's a 2500 4wd and it gets great mileage

But I like the 3.6 in my jeep with the top off
Not having to hear the constant rattle
And smell the fumes of a diesel
Well, if off road for you is just a few miles going over obstacles to see if you can, then any engine is fine but a Diesel is still better. If Off road is an African Safari vehicle, long distance traverse of tough terrain then a diesel is a must. And even you rock crawlers would appreciate the steady low end power. Many of your 4.0L sound like diesels once that tick gets pronounced...

In terms of noise, have you heard the 2.8l CRD in the Wrangler? You will smell more gas fumes on a cold 4.0l than diesel fuel on a CRD. It is not as loud as a Cummins. The Wrangler was never a good vehicle choice if a quiet ride is what your after, road noise is probably louder than any Diesel. The 3.6L gets 10 MPG less than the Diesel with less torque where you want it. Bringing spare fuel is considerable more dangerous with gasoline as a fuel.
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Unread 12-22-2011, 03:26 PM   #94
Matoskah
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Is the 2012 a "Flex Fuel" engine???????
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Unread 12-22-2011, 03:27 PM   #95
Fellstar
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Quote:
Originally Posted by Matoskah View Post
Is the 2012 a "Flex Fuel" engine???????
No.
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Unread 12-22-2011, 03:58 PM   #96
vincejeep1
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The new diesel engines have to have a Diesel particulate filter and it has to be serviced if you don't service it or ignore the service engine light then once it gets shut off it wont restart and has to be towed to a dealer and serviced,reprogrammed before it will start . This is also what happens on 2010 and newer semi trucks
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Unread 12-22-2011, 04:16 PM   #97
Mictrik
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Quote:
Originally Posted by vincejeep1 View Post
The new diesel engines have to have a Diesel particulate filter and it has to be serviced if you don't service it or ignore the service engine light then once it gets shut off it wont restart and has to be towed to a dealer and serviced,reprogrammed before it will start . This is also what happens on 2010 and newer semi trucks

Is this a problem, Do they fail or introduce complexity? I am all for environmental preservation but if this were to become an issue for an expedition vehicle I am sure there will be a workaround. One needs reliability for off road travel, the complexity added to modern engines is often of negative value.
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Unread 12-24-2011, 01:52 PM   #98
tommy35SS
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A diesel Wrangler might be closer to being a possibility if Jeep follows through on this
http://www.leftlanenews.com/diesel-p...-vehicles.html

Hopefully they pair it with this
http://wot.motortrend.com/we-hear-8-...-6-123839.html

This would be the 1-2 punch to show America what we're missing out on due to some stupid stigma of crappy designed GM diesels from the early 80's, heard they didn't even come with a fuel filter/water separator on them. You could ask any mechanic and he'll tell they did not build those cars right
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Unread 12-24-2011, 03:10 PM   #99
Mictrik
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Quote:
Originally Posted by tommy35SS View Post
A diesel Wrangler might be closer to being a possibility if Jeep follows through on this
http://www.leftlanenews.com/diesel-p...-vehicles.html

Hopefully they pair it with this
http://wot.motortrend.com/we-hear-8-...-6-123839.html

This would be the 1-2 punch to show America what we're missing out on due to some stupid stigma of crappy designed GM diesels from the early 80's, heard they didn't even come with a fuel filter/water separator on them. You could ask any mechanic and he'll tell they did not build those cars right
Well, I hope so as I would like to have the option of a 4 door wrangler Rubicon with a Diesel & strong Auto or Manual transmission.
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Unread 12-24-2011, 04:02 PM   #100
JKRazz
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I have a 2012 JK Unlimited Rubicon with the new 3.6 Pentastar...all I can say is "WOW"! It is a serious improvement and can't be called anything less than needed in the JK Unlimited. It had got a ton of power and is got it at all speeds.
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Unread 12-24-2011, 04:23 PM   #101
Panhead5
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The pentastar is a big improvement over the 3.8 but I would not hold my breath for diesels.This country is so diesel unfriendly right now and most folks idea of a diesel and the realities of the modern emissions choked/strapped diesels are a far cry apart.
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Unread 12-25-2011, 04:37 PM   #102
Mictrik
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Originally Posted by Panhead5 View Post
The pentastar is a big improvement over the 3.8 but I would not hold my breath for diesels.This country is so diesel unfriendly right now and most folks idea of a diesel and the realities of the modern emissions choked/strapped diesels are a far cry apart.
No Diesel no Jeep for me, and if the Diesel is indeed so "choked" I again will not purchase one. I really liked the the model offered in Europe. When I wish to have one I will either buy an older stock Rubicon model and install a 2.8 Diesel as parts are available or I will simply get an older Defender. I find it strange how the best off road vehicles are not available state side. The Defender and the real Toyota FJ's are not sold in the States. The FJ cruiser is not in the same class as the others.
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Unread 12-25-2011, 05:12 PM   #103
dwink
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I just traded in a BMW 335d on my Jeep. I loved the powertrain on the BIMMER 3.0 Liter twin turbo diesel with 265 HP and 425 pound feet.

It also revved pretty good for a diesel, although I can say that I enjoy revving the pentastar, I missed that with the BMW (although my 911 still cures the itch best!!).

I miss the swell of torque that the BMW produced, and it would be a great compliment to the Rubicon if Jeep was able to design a similarly good diesel powertrain.

The BMW would see 29 MPG in the city regularly and I once got 43 MPG from Reno to Vegas - and I was going 80 most of that trip. It is a 3900 pound sedan so the Jeep would be almost the same weight....

I would certainly consider a Wrangler Diesel if it were like that...
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Unread 12-25-2011, 05:59 PM   #104
tolnep
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you will not be allowed to buy a diesel jeep. our minders in the congress have rightly assumed that they know whats best for us and that diesel poisons the children. so no diesel jk, no diesel toyota, no diesel bmw 130d.

and if they do decide to allow those here, they will raise the price of diesel so much that no one will buy these cars.

every year the government gets better at protecting us from ourselves. and taxes us more to enable them to do so.
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Unread 12-25-2011, 07:18 PM   #105
i82much
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I get that a diesel would have greater range. However, I find strange comfort in knowing with a gas motor I can run down the battery on a freezing cold day, add some starting fluid and have a decent chance of pop-starting that bad boy.

As I recall, in the old days you didn't need any electrical power at all for a diesel since they didn't have an ignition and used a mechanical fuel pump. I don't know for sure (lazy googler) but I have to doubt that's the case anymore.
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