JK Engine Swap
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JK Newbie
Joined: Feb 2011
Posts: 33
Likes: 0
From: Statesville, NC
JK Engine Swap
I have a 2010 JKU with 170k on the clock. I have been very torn with what the next power plant to install. Has anyone installed the 4.1L 505 performance stroker kit? I have kicked around the idea of a 3.6L with a Prodigy Turbo setup since its more power and torque than a Hemi. I have all the means to do all the work myself however I just would like guidance or some feedback if anyone can give me some. My rig will be on 40s, 60 front and 80 rear, and armored so she isn't petite be no means. I would love to get 400hp to the ground. I have had amazing service from the 3.8L just know that the NAG trans is a weak link. Has anyone ran the ATS upgraded Nag Trans?
JK Jedi
Joined: Dec 2010
Posts: 5,642
Likes: 486
From: Knoxville
There have been a couple of threads on the 505 performance motors. It seems that you get folks that are mad about what they received being quick to register and bash the company then they don't resurface or otherwise add content to the community. I find it tough to take their word when they've been around for 10 days with just as many posts and all of them are bashing a single company.
That being said....I'm high mileage like you are so I'm always watching to see what various folks are doing so I can make an informed decision when my time comes.
That being said....I'm high mileage like you are so I'm always watching to see what various folks are doing so I can make an informed decision when my time comes.
Former Vendor
Joined: Jan 2012
Posts: 452
Likes: 1
From: Wellington,FL
The trans that is equipped with the 3.8L engine is a 42RLE not the NAG1. I have found that this is without a doubt the weakest link to the 2007-2011 3.8s. The NAG 1 trans has proven to be incredible. We lost our in house NAG 1 at just over 500RWHP! The 42rle can fail at any time. The overdrive clutches will go first.
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JK Enthusiast
Joined: Aug 2012
Posts: 266
Likes: 10
From: Myrtle Beach, SC
Not saying one is better than the other. Happy trouble free Hemi swapper here. Pretty much plug and play. And cheaper to swap in than an LS. Never had any issues. 505 stroker seems disastrous from what I have read. I considered a supercharger but soon realized for not much more dough I could have a V8, so that’s what I did.
JK Jedi
Joined: Apr 2010
Posts: 4,468
Likes: 221
From: SE Michigan
Not saying one is better than the other. Happy trouble free Hemi swapper here. Pretty much plug and play. And cheaper to swap in than an LS. Never had any issues. 505 stroker seems disastrous from what I have read. I considered a supercharger but soon realized for not much more dough I could have a V8, so that’s what I did.
JK Enthusiast
Joined: Aug 2012
Posts: 266
Likes: 10
From: Myrtle Beach, SC
At the time of my swap, the install kit was significantly less than the advertised price of an LS kit. I could not find a motor and transmission combo(LS) that was as inexpensive as the $3k I spent on my complete dropout, that came with a transfer case that I was able to sell. Prob could have paid less but the poor 19 year old kid and his GF were expecting. A child and I could not do that to him. Seemed as if the LS required many additional parts that were not included in the kit. Was not plug and play, at the time. In my opinion the 5.3 may be a 300k mile engine but I felt as if to get the 400HP of the Hemi I would have to pour more funds into the 5.3 or go 6.2, 6.0 which made the cost rise substantially. Sure there is tons of aftermarket support, k did not want to get into something I may have to sink even more dough into to get what I expected. My wife has a 5.3 Yukon and it is nothing to write home about. It does get better mileage but not near as fun. I could get 15+ easy on the highway if I had gears a little lighter than my 5.38’s and 37’s. 60MPH or less just under 15 easy, get to 65 and that is different story. 4.88’s would improve it I am sure. But I am very happy overall with my swap. I still grin when I hear it start. After selling the old parts I have about $6800 (8700 before)in it. Among others I believe it could actually be done even cheaper especially if you can do a little fabrication yourself. This was my first experience with anything remotely even close to something of this magnitude. If I had to it over again, I would have installed the 6.4 headers right off the bat. Eventually I will install them, they have been on my toolbox for a year and a half. Also, I have yet to see an LS swap thread where anyone says they have that far south of $10k in theirs.
