So the rattle got shimmed out today. Let it run for about 20 minutes to let everything get up to operating temps. Everything held fine. It’s got a nice little chop with the mild cam. Didn’t go on a drive though. Smelled like it could be running a little rich so just to be safe we’ll wait it I’ll we get it on the dyno to do too much. Really hoping schedules let us get on the dyno this week but we’ll see.
6.1 LJR Build
- Thread starter Gassiper
- Start date
Picking it up tomorrow. Tom’s is completely done with the swap and the only thing left is some dyno tuning. They’ve got a few other projects that won’t allow them to get the Jeep down to Injected within the next few weeks so to help them out I’m going to just take it down myself. It’ll be loaded up and ready to go the first of next week. Hopefully Monday or Tuesday we’ll get the call and head down. In the mean time I’ll get some better pictures of all the work and wash it for the first time in about 5 months.
That's great.!!
It'll give you a little time to give it a shake down and get a few miles on it then before you take it.
Can't wait to here your thoughts after your first drive....
I also seen on YouTube last night that there is a guy doing a 5.7 Grand Cherokee HEMI swap on a 06 white LJ right now in progress. He is switching from the 6 speed to the 545RFE transmission. It's already quite a build with 1 ton Ford axles and 40" tires.
Awesome. None of us really know what kind of power mine will make. It’s the first one they’ve done with a relatively stock drive train.
It'll be double the power at the minimum which you'll feel every bit of that when you lean on the juice pedal...
Definitely let us know your thoughts after you take the first drive..
Also, did they upgrade/upsize your fuel line from the tank to the engine?
The identical swap before mine with 4.88 gears and 37s made 372 at the tires. It also had a mild cam done to it. I hope for at least that. We did not touch the fuel lines.
Believe it was an 05 also. Non rubicon but it was on tons. Same 6.1 swap though.
Sorry, I meant what year is your LJ? I was wondering that because of your comment about not changing your fuel lines.
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Even though it’s not running right yet it just feels good to have it back at my own shop. Like I said, I’ll post final numbers and video of the dyno but the little chop it’s got sounds great. Scheduled to be there Wednesday morning and I’ll drive it back to get some break in miles on everything.
And before anyone asks…the EcoDiesel Grand Cherokee didn’t even know it had a trailer on it.
And before anyone asks…the EcoDiesel Grand Cherokee didn’t even know it had a trailer on it.
Nice.....
I was just asking about the fuel line because I didn't remember you posting anything about them changing it.
Everything I've read, seen, heard, tasted, touched, envisioned and etc. Says the stock 4.0L Jeep 5/16 diameter fuel line will not flow enough volume at higher RPM's to keep up with demand from the HEMI's and will fall short on the top end. I assume that's why the HEMI vehicles run the 3/8 diameter line.
Nashville, did you upsize yours?
I guess we’ll find out Wednesday. They’ve done a lot of these swaps, and never once mentioned anything about having to touch the fuel lines. When I first started talking with them, I asked if the fuel pump or anything else would need to be changed and they said no. I messaged the guy that had his done right before mine to see what he says since he’s been driving it for six weeks or so. I’ll be curious to see if he has noticed it feeling like it’s starved for fuel or anything.
Spoke with the owner of the one done just before me. He’s only driven it but about 100 miles since it was finished. Said he rarely keeps his foot out of it when he does drive it but he’s had no issues at all with it starving for fuel or anything.
That’s actually why I asked about the year. The fuel pump on the ‘04 (mine) and prior does not make enough pressure for the Hemi. And the 5/16” lines are not big enough. However, the ‘05 and ‘06 pumps make 59 psi - which is what the Hemi requires. I run 59 psi pump, and I swapped the lines to 3/8’.
I don’t know the line size on the ‘05 and up - but I was thinking it may have been increased to 3/8 - but working from memory I don’t recall. Everything I know says that 5/16 is not enough for a stock 5.7, much less for my 392.
The danger is that if you are humping on it and the fuel can’t keep up, you can easily go way lean and smoke the mill.
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Yes, that is all the same information that I have gotten before doing my conversion. Mine is an 05 so as you state it has the high pressure fuel pump but the fuel line did not increase and remained at 5/16 in. In fact the feed line from the tank to the steel fuel line inside diameter only measured about a quarter of an inch. The fitting on the 05 and 06 fuel pump is a 3/8 quick release fitting, so I ran a new 3/8 ID fuel line one piece from the fuel pump all the way up to the fuel rail. I know that even Chris at hotwire had told me when he had his hemi TJ and would run it at wide open throttle it would run lean on fuel because he kept the stock fuel line. I know it's not a big deal to change it but I went ahead and did mine while I was doing everything else and had easy access to the fuel pump. It will be interesting to see what his results on the dyno are to see if that was really needed or not, but I went ahead and did it anyway because it made sense to me.
Had to move a harness plug at the back of the motor. It was making contact with the back of the intake and started to take the powder coat off. Let it run for a little bit to get everything up to operating temps and make sure it’s still good for Wednesday. Came back out after about 5 minutes noticing the body shaking from the cam! Hahaha! I didn’t expect it to shake like that but thought it was hilarious. Doubt it’s idle will change after it’s been tuned but heres a quick video of it running, the completely finished engine bay and how well everything tucked away underneath.
I refreshed looking for it but all I found was this post.