V8 Magnum Swap

Advanced Adapters is where I read about the 1" body lift.

It does say recommend not required. Part of this depends on how much you are willing to BFH with a lot of hammer 🔨 and how much you want to cut and mold around drivetrain parts.

Body lift seems easier but I have read some don't install one.
 
just curious, but why go with the 5.9L vs the seemingly more common 5.3 LS?
Because with the Dodge motor the PCM for the V-8 talks to the stock dash. There is some wiring that needs to be redone but it isn't anything like doing a LS swap. It is also more economical than a LS swap.
But Dodge stopped making the magnum V-8 in 2002 with very few in 2003 so if you're trying to stay EPA legal if you own a newer TJ you either do a LS or Hemi swap.
 
Oh its worse then that I am swapping in a 5.2L. :cool: I have a reputation of making bad decisions. But I found a ZJ for $500 and thats pretty much why i chose it. The Magnum motors have been swapped and well documented.

gotcha. I just didn't know if there was some advantage to it that offset the 40-ish horsepower and probably 5mpg deficit it has vs the LS. But "I already have the donor vehicle" is a good enough reason I suppose.

I've been swap-curious for a long time but I'm still 3 years out from having what I consider adequate facilities to do one (my HOA limits number of vehicles parked outside and entirely forbids non running vehicles parked outside, which means I need to build a shop to have room for the donor and recipient vehicles) . I always figured I'd go with the LS but if there was something about staying Mopar that made things significantly easier or produced a superior final result I could definitely be swayed.
 
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gotcha. I just didn't know if there was some advantage to it that offset the 40-ish horsepower and probably 5mpg deficit it has vs the LS. But "I already have the donor vehicle" is a good enough reason I suppose.

I've been swap-curious for a long time but I'm still 3 years out from having what I consider adequate facilities to do one (my HOA limits number of vehicles parked outside and entirely forbids non running vehicles parked outside, which means I need to build a shop to have room for the donor and recipient vehicles) . I always figured I'd go with the LS but if there was something about staying Mopar that made things significantly easier or produced a superior final result I could definitely be swayed.

I'm not sure where you got the 5 MPG better milage from but my only experience with a LS engine was in a truck with a 6.2 and I hated that engine.

My 5.9 stroked to a 6.7 won't be any slouch for power. I'll agree the LS engine can be a good engine but with the ease of the Dodge magnum V-8 swap unless you have a newer TJ I'd still go with it. With a little bit of engine work you can be making 300HP/Torque.
Plus I like being different. And Jeep/Chevy engine swaps are just too sheepishly to me.
 
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Because with the Dodge motor the PCM for the V-8 talks to the stock dash. There is some wiring that needs to be redone but it isn't anything like doing a LS swap. It is also more economical than a LS swap.
But Dodge stopped making the magnum V-8 in 2002 with very few in 2003 so if you're trying to stay EPA legal if you own a newer TJ you either do a LS or Hemi swap.

ok, that's what I figured.

When I get around to doing a swap, it'll probably be going into an LJ, but my county in Colorado doesn't care what I do with it as long as they get their registration renewal fees.

What kind of change in mpg did you see vs the 4.0? I don't drive mine enough for it to matter financially, but I'm not sure I'd want to decrease my range much further.

I assume a hemi into a 2004 would have the same advantages against the LS with respect to the PCM/instrument panel interface? Still, range between fillups being a possible concern. A 2004 Ram hemi was EPA rated for 14mpg combined, vs 16 for a Wrangler. Those LS engines just so dang efficient. <EDIT: in my next post I discovered the difference isn't as stark as I thought>
 
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I'm not sure where you got the 5 MPG better milage from but my only experience with a LS engine was in a truck with a 6.2 and I hated that engine.

My 5.9 stroked to a 6.7 won't be any slouch for power. I'll agree the LS engine can be a good engine but with the ease of the Dodge magnum V-8 swap unless you have a newer TJ I'd still go with it. With a little bit of engine work you can be making 300HP/Torque.
Plus I like being different. And Jeep/Chevy engine swaps are just too sheepishly to me.

My mpg comparison was unfair. I saw the 1999 Ram 4x4 5.9L was EPA rated for 12 combined, and compared that directly to my real world results with the Silverado which sees mostly highway miles. The Chevy was only rated for 14, so I wasn't comparing apples.

Power-wise, I'm just comparing stock for stock. I have a 2000 Silverado 5.3 in my driveway, get about 17.5mpg with it and it was published to have 285hp vs 230-250 for the 5.9 Magnum depending on the year. Yeah, 6.7L will be no slouch, holy moly! And though noise isn't what I want in a Jeep, Mopar motors always sound way better to me than Chevys do. They have that gorgeous musclecar roar where Chevys to me sound like an old farm truck with glass packs.
 
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I'm not talking about your local EPA laws I'm referring to Federal EPA standards. If you swap a engine from a older model year than the year of the vehicle it's being swapped into it's illegal to sell it. Plus if for some reason they did start doing smog checks where you live would you want to not be able to license it?
Keeping it smog legal IMHO doesn't hurt performance so why not keep it legal.

Yes the Hemi can be made to talk to the stock dash easier than a LS.
You get about the HP numbers from either.
You can't use the MPG rating from a heavier vehicle to compare in a Jeep.
I didn't have a 4.0 I had a 2.5. But on trail runs I used about the same amount of fuel as others with a 4.0. Plus I'm running 38" tires compared to their 33-35" tires.
 
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My mpg comparison was unfair. I saw the 1999 Ram 4x4 5.9L was EPA rated for 12 combined, and compared that directly to my real world results with the Silverado which sees mostly highway miles. The Chevy was only rated for 14, so I wasn't comparing apples.

Power-wise, I'm just comparing stock for stock. I have a 2000 Silverado 5.3 in my driveway, get about 17.5mpg with it and it was published to have 285hp vs 230-250 for the 5.9 Magnum depending on the year. Yeah, 6.7L will be no slouch, holy moly! And though noise isn't what I want in a Jeep, Mopar motors always sound way better to me than Chevys do. They have that gorgeous musclecar roar where Chevys to me sound like an old farm truck with glass packs.

But again that isn't a fair comparison. Compare a Chevy from the same years.
 
I'm not talking about your local EPA laws I'm referring to Federal EPA standards. If you swap a engine from a older model year than the year of the vehicle it's being swapped into it's illegal to sell it. Plus if for some reason they did start doing smog checks where you live would you want to not be able to license it?
Keeping it smog legal IMHO doesn't hurt performance so why not keep it legal.

Oh I totally agree. and I never know when I might change jobs and move somewhere that does care, so I'd want to keep it clean and legal.

Yes the Hemi can be made to talk to the stock dash easier than a LS.

honestly that might have just sold me.

You get about the HP numbers from either.

yes

You can't use the MPG rating from a heavier vehicle to compare in a Jeep.

agreed. I'm just applying the logic:

1. if engine A gets better mpg than engine B in similar vehicles (in this case a half ton, extended cab 4x4 pickup), then engine A in a TJ should get better mpg than engine B in a TJ.

2. An engine will get better mpg in a TJ than in a full size truck, which leads to:
a. If engine A gets better mpg in a half ton pickup than engine C gets in a TJ, then it will definitely get better mpg in a TJ than engine C

b. if engine B gets worse mpg in a half ton pickup than engine C gets in a TJ, then no conclusion can be drawn and when installed in a TJ, engine B may get better, equal or worse than engine C.
 
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All very true. I can only tell you what others have said about doing this swap. Those who have replaced their 4.0 engines with either a 5.2 or 5.9 have said they are getting the same and sometimes better fuel mileage than the stock engine. If you have larger tires and have been running the 4.0 that way I'd guess you were lucky to see 12 MPG so because you don't have to have your foot buried anymore your fuel mileage might improve with a V-8 swap.
Yes the LS engines are more fuel efficient than the Dodge magnum engines. This is a given. But with a better tune on the PCM & some roller rockers some have reported better MPG & a increase in power. Dollar for Dollar the LS is going to make more power than a Mopar engine. But how long will it take to recover your money spent after doing the LS swap? But again if you have a 2003-2006 TJ/LJ then you either have to go with a LS or Hemi and either swap is going to cost about $10K as a rough figure.

The reason many with older TJ's go the Dodge route is because of the ease of this swap. And not having to run 2 PCM's to keep your stock gauges if you got LS is one reason. Bottom line go with the engine you want but research it before you do the swap. Just because you happen to have a wrecked Ford van siting out back isn't a reason. Dodge Dakota/Durango/Ram vehicles are coming down in price so they are all good candidates if you have the same year or older than the donor rig. I went with the Dodge V-8 because at the time a Hemi engine was ubber expensive and there wasn't much support for the LS engine. The 6.2 I had was in a 3/4 ton truck and I was lucky to ever see better than 12 MPG out of the thing and the power was not impressive at all.

The 6.7 stroker engine I am building has cost me very little. I paid $50 for the 5.9 rebuildable engine and then I traded a short block for the stroker short block. I'm building the engine for torque not HP but am still going to run some performance parts in it. And I have a built 46RE transmission to handle the power. Similar builds have hit 450-500 HP/TQ at the crank. I think that will be enough to motivate my Jeep even with the larger tires.
If you have the time and money to build a 5.2/5/9 right they can make some good HP/TQ numbers. Once I get mine running and can give some real numbers I'll let the forum know what type of fuel mileage I'm getting.
 
If I were building an older jeep, like a cj7, there is no way I would put a magnum 5.2/5.9 in it. 5.3 Chevy with a small cam, 4l65e trans, and motor on. The reason is most CJs need to be completely rewired at this point, so so are basically starting over anyway. This would include YJs also.

TJs are another story. If you want over 400 hp cheap( relatively) put a chevy in it. If you want an swap that is easy to make look factory, do a magnum. It's easy as far as v8 swaps go ( I have done ls, small block chevy, small block ford, magnum) , no t case adapter required, uses the same basic pcm, gauges work, etc


Now before the ls crowd jumps in, yes, it is a badass platform. But, it isnt as easy or inexpensive as a magnum ( in a TJ ).If I were building a no holds barred, let's go son of a bitch I would use a ls Chevy. My Tj with a 5.9 and a little cam runs with the AMCs and SBChevy CJs my friends have. I cant run with the 5.3 or 6.0 Chevys.

It's all doable and all engines have their pros and cons.
 
A little EYE CANDY.......


This is the intake that is going on my engine. It is made by F&B Throttle Bodies

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If I were building an older jeep, like a cj7, there is no way I would put a magnum 5.2/5.9 in it. 5.3 Chevy with a small cam, 4l65e trans, and motor on. The reason is most CJs need to be completely rewired at this point, so so are basically starting over anyway. This would include YJs also.

TJs are another story. If you want over 400 hp cheap( relatively) put a chevy in it. If you want an swap that is easy to make look factory, do a magnum. It's easy as far as v8 swaps go ( I have done ls, small block chevy, small block ford, magnum) , no t case adapter required, uses the same basic pcm, gauges work, etc


Now before the ls crowd jumps in, yes, it is a badass platform. But, it isnt as easy or inexpensive as a magnum ( in a TJ ).If I were building a no holds barred, let's go son of a bitch I would use a ls Chevy. My Tj with a 5.9 and a little cam runs with the AMCs and SBChevy CJs my friends have. I cant run with the 5.3 or 6.0 Chevys.

It's all doable and all engines have their pros and cons.

If I was building a CJ or even a YJ I'd put a TPI 350 stroked to a 383 in it. But that is because I've always liked that engine. And as I said my only experiance with the LS engines was the 6.2 I had and it SUCKED. It wasn't good on fuel and didn't have the power I thought it should have had.
 
Here are some driveline and exhaust pictures for you.

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Then here is the driveline.

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Edit: Okay I don't know why it is showing all the pictures twice. But you get the idea.

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If I was building a CJ or even a YJ I'd put a TPI 350 stroked to a 383 in it. But that is because I've always liked that engine. And as I said my only experiance with the LS engines was the 6.2 I had and it SUCKED. It wasn't good on fuel and didn't have the power I thought it should have had.

To clarify, you had a 6.0 in that 3/4 ton you drove. GM never put their 6.2 in the heavy duty trucks as it is their performance model.

the 6.0 stock is anemic like the base 5.3. Both are good engines, last a long time but down on power compared to the more modern engines.

I’m not a GM fan boy. My neighbor had a Denali and and has the 6.2 in it. It’s a god damn fast truck.
I have a F150 with a 3.5 eco. I keep telling him we need to line up, but I’m might add a tune to blow his doors off. The 6.2 is a beast, but not a workhorse like the tied and true 6.0 was. And yes, it wouldn’t blow up your skirt but GM makes junk transmissions too in that era. Lol.
 
Here are a bunch of notes I gathered from other people's swap threads on what they did with the wiring. None of this information has been verified but it is what others shared. So please use it at your own risk and take the time to check any suggested wiring mods BEFORE you do them. I'm just trying to share what information I have.
 

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