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Discussion Starter #1
hey yeah, well, as u may know, i am getting the jeep when i graduate highschool woohoo :) and we all know the jeep is way underpowered with 4:10 gears. But, if possible, I would like to take an old 350 out of maybe a K5 and drop it right in the JK. If people can fit a hemi int here, then most likely, you could fit a smallblock. It might be dump question, but hell, why not.

alright, thanks - Mike
 

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hell with enough $$$$$$ a briggs and straton could be powering a jeep. i swapped in 350 in my YJ but with so much of the jeep controlled by computers it would be a pain in the ass to get all the stock gauges to work and 1/2 the electronoc crap insode prob would stop working alsp
 

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Discussion Starter #3
ohh true. bnut the payload would be definately worth it. But isnt Cummins making a 2.8L diesel that would also fit in there?
 

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big thing is are you gonna use it on the street as well or just a trailer queen? Depending on where you live you have emission standards to follow and rules about swaps. Xtreme4x4 just had a great show with a lot of information swapping a Hemi into a TJ. Something about engine has to be from the same maker, like a chevy engine in a Jeep wouldnt work, has to be same year or newer and new ECU flashed with the VIN# of the Jeep. I think this was for Cali standards though...
 

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big thing is are you gonna use it on the street as well or just a trailer queen? Depending on where you live you have emission standards to follow and rules about swaps. Xtreme4x4 just had a great show with a lot of information swapping a Hemi into a TJ. Something about engine has to be from the same maker, like a chevy engine in a Jeep wouldnt work, has to be same year or newer and new ECU flashed with the VIN# of the Jeep. I think this was for Cali standards though...
Hah! I saw the same show. It's funny all the stuff you can pick up from that show.
 

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Discussion Starter #8
ohh alright, but yeah the jeep wouldnt be my daily driver. it gets what 13 mpg as it is stock, but i think theres soemthing wrong with the tranny. i have the 4spd automatic, and once it sets into 3rd gear (60mph+) u basically lose the ability to get up and go.
 

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Hah! I saw the same show. It's funny all the stuff you can pick up from that show.
Not all the info is entirely true across the board.
Swapping a GM engine into a Jeep is possible.

We have 3 Jeeps out back all running CA smog legal GM engines.
This may not be true for all province/countys in the USA but in most areas it is legal. Check with your local DMV/Smog referee for more info.

However I wouldnt put anything less than the equivelent year engine into the vehicle.
2007 JK = 2007 or newer engine. (the TJ GM engine swaps are easy) JKs on the other hand, you might as well kiss everything electronic goodbye, at least for now.) :grinpimp:
 

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but i think theres soemthing wrong with the tranny. i have the 4spd automatic, and once it sets into 3rd gear (60mph+) u basically lose the ability to get up and go.

Its the lack of horsepower. :pissed: Manualy shift it to make it feel more responsive. also if you turn O.D. off it will lock the torque converter sooner and make it feel like a dog.

Can you ship your parents to me. I want a JK. :laughing:
 

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Its the lack of horsepower. :pissed: Manualy shift it to make it feel more responsive. also if you turn O.D. off it will lock the torque converter sooner and make it feel like a dog.

Can you ship your parents to me. I want a JK. :laughing:
It's not the lack of horsepower that makes a stock JK feel sluggish...it's the drive-by-wire system limiting the output.
 

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I understand "drive-by-wire", but why does that limit out?
 

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Let me clarify a little since I see that it can be a little confusing the way I worded my response...

Pertaining to when I said the drive-by-wire system limits the output, what I mean by that is that when driving up a long steep grade you can have your the pedal on the floorboard and you won't have any increase in speed or rpm, and you may even have a drop if the hill/mountain is steep enough (I've noticed that to be the case with my 6spd Rubi with 35's in 6th gear traveling up over mountains in Utah). Is it that the power isn't there? No. There is plenty of power to be had, but due to the size of tires and gearing, the electronic wizardy just won't output any more power without making you shift down into 5th. The reason being is because, as stated by Jeep Engineeers, "Much of the 3.8L's power is made at higher revs - it takes power to keep steady speed on hills and the 3.8 needs to be kept up in the powerband." The 35's definately contributes to this since it isn't an inital design factor when the engineers originally made the Jeep.

Here's a link to the Jeep engineer's explanation, as stated above, along with the original question that prompted their answer (which is pretty much the same idea here). http://www.jeepforum.com/forum/showthread.php?t=513743&page=8. Scroll to post #117. Hope this helps.
 
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