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Wrangler Magnum V8 Discussion

712K views 3K replies 133 participants last post by  wildman4x4nut 
#1 ·
Just finished up the most recent swap..this was done in my 2003 TJ..I'm cuurently done with the swap, had it started up in 2 days then got busy with other stuff but only had small things to do to it..fluids and tidying up ect... This is more of a discussion thread instead of a build thread. I'll answer questions or whatever..and help if I can.

Here's the swap parts I used.

99 5.2 Magnum motor (bought a Durango as a donor)
Durango V8 Throttle Cable
Motor mount kit - (AA part# 713094)
Fuel line frame to engine (52127819AE) (If you don't have one)
Oconeeoffroad V8 Conversion Radiator (GM Syle)
Dodge 318 V8 Tj Headers (summitracing.com or Novak-adapt.com)
Electric Fan (I used the Fal Black magic 180, however you can also use part# CBG4F250 from summit..it will bolt into the wrangler 4.0 fan shroud)
94-99 Dodge 3.9 V6 Bellhousing (Bolts up to the V8 and AX15 or Nv3550)

If you use the 3.9 bellhousing and the jeep ax-15 or nv3550 you will need to do no modification to the drive shafts or shifter everything will remain in stock location on the Jeep..You simply have to move the AA motor mounts a littler further back when placing the engine..very easily done.

2001 Dodge Ram 1500 5spd Engine Harness

03 Dodge Ram 1500 5.9 ECU (56040491AB) I sent the ECM to Dave Kasper at BGChrysler so he could switch it to a manual transmission, get rid of the skim, and change it from a 5.9 timing/fuel map to a 5.2 timing/fuel map.

00-03 Injectors (since the motor was a 99 and the injector styles changed in 2000)

Zj Power steering bracket
2001 Ram 5spd CPS

7/16x20 flywheel bolts (these are needed for the difference between thickness of the flywheel and flexplate)

Zj power steering pump pulley
Zj Serpentine belt
2001 Ram 1500 flywheel
2001 Ram 1500 clutch
Wrangler 4.0 power steering pump
NV3550 Transmission with Transfer case

Anyway here's a few photos.. I dont have many as I'm too lazy to do work and spectate to take pics..

Getting her torn down..



That was easy...



Now lets remove those stock engine mounts..nothing a little grinder can't handle...





Ok..now lets bolt the engine and tranny all together...





All went together easily...

Finally getting this sucker in place....



I'm missing a few pics here..after I placed the engine the first time I bolted the tranny to the skid and put the driveshafts in..I checked the firewall for clearances then placed the motor mounts where they needed to be and tacked them in...afterwards I yanked everything back out and painted the frame.

And finally in it's final resting place...







I had already previous built the wiring harness before starting the swap so I would have very little down time..after I placed the engine for the final time I hurrily hooked everything up to see if all was good...

here's a short video of beast (as the wife calls it)

http://s1171.photobucket.com/albums/r545/jeepingijoe/?action=view&current=52v8swapstartup.mp4

It started up and ran fine but I had no gauges..so I siphered out some diagrams and tried a few things..it lead me to believe that although my dodge ecm was a 2003 it had to be a CCD bus system..it came from a 2003 ram van 3500 5.9..to make sure it wasn't my harness I plugged the old jeep ecm back in and turned the key..yep the gauges worked...My Ecm is a CCD and not PCI like a need...(I never doubted the harness I have built a few now but you can never be to sure)
Well after that fiasco I looked at the wiring diagrams for the Ram Vans and Ram 1500 in 2003..
I sourced a 2003 Ram 1500 5.9 ecm which is PCI so after that comes in I ship it back out to BGchrysler for them to convert it to manual ect ect. and all should be golden.

I know I'm going to get asked about wiring..all I can really say is get the wiring diagrams and get to work..it's actually pretty simple...but if need be and you want to have someone build it for you let me know..I'll build them for a fee..that is much less than others..
 
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#2 ·
Nice... :thumbsup: I am thinking about doing a Magnum swap this winter. At first I was thinking of a GM LS but the Magnum motor seems the easiest way to go. My 4.0L runs fine but the idea of my Heep with a V8 = :drool::drool::drool:
 
#3 ·
Honestly I'd probably go 4.0 stroker over the v8..while I love a v8 unless you buy a donor vehicle like I did it's just not economical when you already have a pretty good platform (4.0)..I only have around $500 in mine that's everything..I saved alot by parting out the donor..:2thumbsup:
 
#5 ·
It's good to know that the automatic, pci data bus computer can be reflashed to use in a manual. I want to do a 360 swap in a 2003-2004 rubicon with the nv3550 transmission. I couldn't get a clear answer if the auto to manual reflash would work. What did they charge you to do the flash? Did you cut and splice the harness or repin it?

I have been gathering parts to do a magnum 360 swap. So far I have the 3.9 bell housing, 2002 360 with 80,000 miles, engine harness, 2002 dodge ram computer.
 
#7 ·
I can't tell if there is a difference in strength between the nv3500 (dodge truck) and the nv3550 (2000-2005 wrangler). The only difference I can tell is the nv3550 has a removable bellhousing. If that's the case i'm wondering if that would be a better choice for my swap because I'm hoping I don't have to cut a new hole in the floor and modify the transmission mount.
 
#8 ·
dude this is an awesome swap #1 cuz its a Mopar motor, and #2 cuz its pretty much direct fit.... My question is, and im sure you do, but any Check engine light??? And if so are you tryin to get rid of them?? Im in cleveland ohio and we have emissions.. it would be cool to do that swap w/ a built 318 and not have any check engine codes so it can pass emissions
 
#13 ·
yes i know that but if it was me i would say screw it ha.... im sure he can get some lines made to fit to the stock setup if he wants..... If hes even using the stock radiator and condensor
 
#16 ·
2006_Sport said:
I would love to find a durango with the v8 in decent condition with an auto. I'd swap it in a heartbeat.
They're everywhere. I just bought a whole running 5.2 Durango with a bad auto (I'm keeping my 5spd) for 500 . Took the motor and am taking it to the yard in 2 days for 400. 100 for the motor? I'll take it! I am doing a total rebuild though.

Sent from my iPhone while I shouldn't be on my iPhone.
 
#24 ·
To all that have done the magnum swap - I would like to get your thoughts/experience on the exhaust system.

I started collecting parts for a 5.2 swap for my 98 TJ. So far I've got the motor from a 99 Durango with the wiring harness, I stripped it down, and pulled the intake and oil pan to get a look into the cylinders and it looked great. I installed a Hughes plenum plate because the motor had a blown lower plenum gasket. I replaced the plugs and wires, removed and cleaned the fuel injectors, painted everything up, and now its more or less ready to drop in.

I've also got a new swap radiator, radiator hoses, fuel line, and patriot block hugger headers fro
Summit. I've still got to get a flywheel, clutch, bellhousing, motor mounts, and PCM.

I also need to get the exhaust sorted. What did you guys do for exhaust? My original plan was to run 2.5" from each header to a y-pipe, then 3" cat, 3" muffler, and 3" tailpipe. I wanted to reuse the downpipe that I have laying around from a magnaflow cat I installed a few years ago. It's 2.5" mandrel bent and would prob be easy to adapt to run the drivers side header to the pass side. I am thinking that I want to run a 2.5" cat, muffler, and tail pipe though. They are easy to find online and inexpensive. Is it a bad idea to run 2.5" pipe from each header only to then run 2.5" all the way back from the y-pipe? Will it really screw up exhaust flow? I don't want to run my current setup because the outlet of the cat is 2.25" and I have a 2.25" catback. Seems too small for the V8.
 
#25 ·
Also, I plan to use a ford taurus electric fan, and i realize that I will need a CPS and fluids and such as well. There are still a few "small parts" I need to collect including a new oil pressure sender because I cracked the old one off the back of the block - those things are flimsy!

Can I reuse my jeep o2 sensors or do I need to buy Durango sensors?

Did you use reuse the 4.0 power steering pump so that you wouldn't have to make new hyd lines? Is the grand cherokee bracket necessary for that? Did you leave the stock 4.0 pulley on it?

Thanks again, I'm sure I'll have more questions as time goes on...
 
#28 ·
I'm also in the middle of this swap. After pulling the stock 4.0, I started on the front suspension. Figured it would be easier with the engine out. It's just a custom mid arm setup. I bought a whole 97 Dakota with 5.2. Even drove it home. I bought a stock 97 jeep wiring harness off eBay so I would have less downtime. The wiring was by far the easiest part. Helps that the Dakota is a five speed and I'm keeping my stock ax15. I dOnt know about the 5.2 fitting with just moving the advance adapters motor mounts aft. My firewall would not let the engine sit far enough to the rear to bolt to the bell housing. I had to move transfer case and trans about two and a half inches forward and fab a new transfer case mount on the skid plate. I also used a zj power steering bracket as I had purchased a PSC power steering pump with the aluminum reservoir a few months back. I have to hook the wiring up to the engine, finish some plumbing, attempt to make the stock exhaust manifolds work and mod the stock shifter since I moved everything so far forward.
 
#29 ·
I should note that I had my engine completely rebuilt. New everything except block and crank pretty much. New heads, cam, lifters, pistons. All new sensors, wires, plugs, etc. I'm sure there are more economical ways to do this but I didn't want anything done halfway. I'm hoping to see if it will run this coming weekend. Lots of little odds and ends to finish. If I had it to do over, solely based on the amount of work, I might have looked harder at a stroker. I chose the v8 mainly because I have always dreamed of a v8 swap and doing it myself. Also because I believe (only opinion with no research) that a stick v8 would be more reliable and durable than a hotrodded 4.0. Plus I think I will get better mileage with the 8 than I did with the stock 6 much less a stroker.
 
#30 ·
dmgiff said:
I'm also in the middle of this swap. After pulling the stock 4.0, I started on the front suspension. Figured it would be easier with the engine out. It's just a custom mid arm setup. I bought a whole 97 Dakota with 5.2. Even drove it home. I bought a stock 97 jeep wiring harness off eBay so I would have less downtime. The wiring was by far the easiest part. Helps that the Dakota is a five speed and I'm keeping my stock ax15. I dOnt know about the 5.2 fitting with just moving the advance adapters motor mounts aft. My firewall would not let the engine sit far enough to the rear to bolt to the bell housing. I had to move transfer case and trans about two and a half inches forward and fab a new transfer case mount on the skid plate. I also used a zj power steering bracket as I had purchased a PSC power steering pump with the aluminum reservoir a few months back. I have to hook the wiring up to the engine, finish some plumbing, attempt to make the stock exhaust manifolds work and mod the stock shifter since I moved everything so far forward.
Can you give any tips on the wiring? I assume you keep the engine harness completely intact and plug it into the dodge ecu? How did you start on the rest of it?
 
#31 ·
Everyone always asks about the wiring, and honestly, it's not that easy to answer. Here was how I did mine: I bought a Factory Service Manual for the donor vehicle which was a 97 Dodge Dakota off of eBay for like $30. I already had a Factory Service Manual (FSM) for my Jeep. I bought a spare Jeep 4.0 wiring harness off of eBay for $85.

When I removed the wiring harness off the donor 5.2, I labeled every single plug, both with numbers and a short description. I labeled the corresponding plug as well if it plugged into something. I then took that wiring harness and stripped all the muddy, greasy, filthy wiring loom and tape off of it. I bought a piece of plywood and I stood it on edge and drilled a couple holes in it so I could zip tie the three big plugs which plug into the ECM to the plywood.

I then ended up attaching the entire donor wiring harness to the plywood loosely zip tying near each plug after drilling holes for the zip ties. Then I took a black sharpie and wrote what each plug was on the plywood. I kept the donor harness on one side of the plywood. Then I took my new (used) 4.0 engine harness off eBay and attached it next to the donor harness on the plywood.

Once you do this (which, by the way was the suggestion of another guy on this forum RDA16 or something like that....) you will see the similarities in the harnesses. There are actually very few differences. This, however, was partially due to the fact that my Jeep is a 97 manual and my donor Dakota is a 97 manual. You get into other issues if mixing auto/manual trans or different years.

Ok, so when it comes to the actual changes on the wiring harness; the only significant change is depinning all your injectors off your stock harness, depinning all the injectors out of the donor harness and repinning them back into your stock harness.

That will get you started. Then what you do is look at the three big ECM plugs and find out what each pin does from the FSM. Then if it doesn't match up from the stock harness/ECM, you have to change it. Just take one plug at a time and follow each wire to each plug to make sure it does what you think it does.

There were a couple other changes on the harness, but I can't remember right now what they were. They were minor, though. The only real change was the injector wiring.

Keep in mind, I haven't actually started mine, so I could be completely effed up and just not know it yet....

Soon.....
 
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