Why the JK 3.8L V6 sucks.....the video!!

alosix

Expedition Leader
I LOVE turbo cars. Have owned and heavily modified 4. Currently have a Porsche 951(944 turbo).

I think a turbo would be ideal for the elevation. Tricky stuff on a "V" platform without doing twins. For simplicity sake I think the Hemi or supercharger would be better.

Although, I did a little research into the "remote" mount turbos. The big problem is that the air intake ends up under the Jeep.

Yeah, the hemi would def be more practical. The 4 door really should have had at least the 4.7 as a factory option.

I do wonder if a reversed header on the 3.8 would allow you to use some of the room in front of the engine since there is a TON now.

My worry here (your current case) would be tranny heat. the video shows it made it up the hill. But that was 2nd gear with the TC unlocked and pulling hard for at least 8 minutes. That's a lot of heat to bleed off. I wonder what your temp gauge would have looked like if it wasn't cold out.
 

Pskhaat

2005 Expedition Trophy Champion
Whooptido for you

Cole, absolutely no need for a response like that.


If we only ever covered a topic once then forums would shut down. Also, show me where the video of the climb from Silverthorn to the tunnel has been beaten to death already?

That I70 stretch is deceivingly steep --my GIS says gross 6%--but clearly there are undulations. The only time I've ever met the speed limit is in an SHO, my old Honda Hurricane, or an old Acura Legend going up that hill, my Ford Probe, Honda Accord, and LC100 don't do it that well at all.

The topic is flogged because (and I'm no fan of that V6) of how fast you're actually going. As mentioned you're at high RPMs as that is where your torque rise is in those engines, ~1000 RPMs higher than the "old" 4.0.

154_0706_03_z2007_jeep_wran.jpg
 

Hilldweller

SE Expedition Society
I hit that stretch in my MINI S and had no problems...

But it did smell like burnt insulation for a while after climbing Independence Pass at a little over the speed limit.
I popped the bonnet and sat there for a half hour looking for meltage.

100_2612.jpg
 

Cole

Expedition Leader
How about a flat-6 and twin-scroll turbo for the ole JK? :coffeedrink:


As a Porsche fan I can appreciate that:victory:

Yeah, the hemi would def be more practical. The 4 door really should have had at least the 4.7 as a factory option.

I do wonder if a reversed header on the 3.8 would allow you to use some of the room in front of the engine since there is a TON now.

My worry here (your current case) would be tranny heat. the video shows it made it up the hill. But that was 2nd gear with the TC unlocked and pulling hard for at least 8 minutes. That's a lot of heat to bleed off. I wonder what your temp gauge would have looked like if it wasn't cold out.


Fortunately, I think the AEV heat reduction hood is helping me vent that heat.


4328379591_9f56456a13_b.jpg
 

Cole

Expedition Leader
I hit that stretch in my MINI S and had no problems...

But it did smell like burnt insulation for a while after climbing Independence Pass at a little over the speed limit.
I popped the bonnet and sat there for a half hour looking for meltage.

100_2612.jpg

Love the Cooper S. (especially the turbo version over the supercharger).


My Audi S4 with this in it did not have much of an issue with the pass either. (photo is actual motor from my Audi, 500hp/600tq)

4074594072_28b8b98487_o.jpg
 

OS-Aussie

Adventurer
I don't think the 3.8 is that great either, but I think the weakest link is the jeeps auto transmission, a five or 6 speed auto in there would probably make the 3.8 fine.

This bit is maybe not to far off. The standard box and gear set does not appear to be a good match. Maybe the Rubicon is better with the 4.11 but he Sahara is not right and kicks out of over drive when birds fly past.

What Jeep should have done.....
3.8 for the mall crawlers
4.7 for jeepers
3.0 MB diesel for expedition

I know which I would trade for in a heart beat.... (have one in the WK) :coffeedrink:
 

TheMike

Adventurer
I absolutely, without a doubt, love my 6.1. It's overkill (and not very practical) for the "expeditition" route but I don't care. I put the fully loaded Chaser behind it and set the cruise at 85. No matter the hill (even the one on the video) is no challenge. I will carry enough gas to make up for the lack of MPG, make sure it's top shape, and head out. Getting there is just as much fun for me as the destination.

I have put one HUGE tranny cooler with thermatic control (175 degree) fan. Honestly, that was my only concern and now I feel covered.

The AEV hood was, from day one of the plan, on my parts list. As with all big plans, costs quickly over ran expectations. With it 40 degrees outside, normal freeway driving, it's 140 degrees going into the air cleaner. I decided to try and do something about that so I made a cardboard "shield" to block some heat and now under the same conditions, or warmer, I'm at about 110 in the air cleaner. The 6.1 is designed to run hot. 210 before the engine fan even turns on. That hood would really help get rid of some of the heat.

There are pros and cons to upgrading the 3.8 to a hemi. For me, the pros far outweigh the cons. It's fun and that was the goal. The 3.8 never was in the cards and I bought the JK and the Hemi conversion at the same time. Yes, the 3.8 sucks (my opinion).

Go HEMI!!!! The way the JK should be available to purchase.
 

Hilldweller

SE Expedition Society
I absolutely, without a doubt, love my 6.1.
Go HEMI!!!! The way the JK should be available to purchase.
Shut up shut up shut up shut up shut up shut up....
....I'm not listening hands over my ears shut up.....


....check book is dangerously close to my left hand.....

:drool:

help...
 

TheMike

Adventurer
I got everything from BOR (Burnsville Offroad). I will tell you this, and if everyone else is honest they will tell you the same thing:

If you go 5.7, go with AEV. Anything bigger, go with BOR.

BOR is the only place I am aware of that can truly be a one-stop-shop. That's only one of the reasons I went is route. There are more reasons but best in another arean (AKA forum). My Hemi build is on a couple other forums but it best seen here on my local club's forum. You don't have to sign up to see it. Cole, come join us. That goes for any other Denver based JK drivers.

I'll answer any questions ya'll have. I don't want to hijack the thread so if there's demand I'll start another thread or you can email me.

Oh yea, here's a little video of me playing after doing Chinaman Gulch (Buena Viast CO) a couple of weeks ago. Turn those speakers up!!

Yes, I almost took out a tree.
 
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TheMike

Adventurer
Here is a little more affordable option. A little over 10k for a 5.7l installed.

http://www.jeepspeedshop.com/
Be carefull if you go this route. I know of both the AEV and BOR kits and products EXTREMELY well. You get what you pay for so keep that in mind. If you are serious, all hemi conversions need the same stuff so really, I mean REALLY look at everyone's kit to see what's different or missing.

I personally know of one individual that I talked with just after I finished my conversion that went the AEV route and bought used powertrain. He too did his in his garage for a total of just over 8K.

It can be done for that. You just have to know exactly what you are looking for and it's really who you know. We, who have done this, are more than willing to dump our knowledge back to you so..

"For those about to rock.....we salute you!"
 
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FreeManDan

Adventurer
I was reading this entire thread like count form sesame street, ONE mention of a diesel! AAH-HAH HAAH! TWO mention of a diesel! AAH-HAH HAAAH!
I don't recall if it was JP magazine or petersen's 4wheel, but it covered the BOR 2.8 turbo diesel transplant. The 5.7 would likely be easier, or just demand from automakers that they cough up a midsized diesel...
 

TheMike

Adventurer
A diesel would be awesome! At the time, and even now, doing a deisel swap is much more extensive and "kits" are very sketchy. There's only so much "experimenting" I wanted to do for my daily driver. Besides, I'm not the most patient man and I WANT MY ******** NOW!!! :)

They will come, I know it.
 

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