Need some help on an engine swap

Area for General NON-Jeep related chat. Topics are typically not moderated, but must fall within the Use Guidelines.

Topic author
nylajean44
Posts: 13
Joined: Sun Sep 11, 2022 2:54 pm
Location: Ontario, Canada

Need some help on an engine swap

Post by nylajean44 »

Hey fsj network i need some help. I’m looking into swapping my engine out of my 1987 jeep grand wagoneer, i came across a 5.9 v8 out of a 1999 dodge Dakota rt but the transmission is a 2 wheel drive. This is my first time swapping an engine and I don’t have a clue on what I would need to make that engine work with my transmission. Anyone that can help me out?
1975 Jeep 10 AMC 5.9, dealership special
1987 Jeep Grand Wagoneer AMC 5.9 (no longer own)

Johnzi10
Posts: 256
Joined: Wed Nov 25, 2020 9:43 pm
Location: Northern Kentucky

Re: Need some help on an engine swap

Post by Johnzi10 »

The AMC 360 is different from Chrysler 360. I have not swapped anything, but I’ll bet engine mounts are different and no guarantee on trans match.
2020 Cherokee Limited v6. Wife’s Jeep
2002 Grand Cherokee Laredo Daughters Jeep
1998 XJ Cherokee “the Ghost”
1989 Grand Wagoneer my Covid mental health medicine
User avatar

Scotty54
Posts: 98
Joined: Sat Dec 10, 2022 6:08 pm

Re: Need some help on an engine swap

Post by Scotty54 »

Nylajean - while engine swaps are somewhat common with FSJ's, the Mopar 360 isn't. I have never seen adapter kits but have never looked either. Small block Chevies are far more common, and lately the LS versions have taken hold, and for good reason - it is a terrific engine. I don't think the Mopar 360 has the same reputation but any swap is possible. Considering the cost and difficulty, the Mopar 360 may not be your best choice.

Swapping is a little more common among CJ owners who desire a V8 over their six cylinders. You may want to query some CJ sites.
1977 Cherokee Chief 401 QT
Northeast Tennessee
User avatar

tgreese
Posts: 7118
Joined: Fri Jun 08, 2012 6:31 am
Location: Medford MA USA

Re: Need some help on an engine swap

Post by tgreese »

A Chrysler 360 is the LA engine; 273, 318, 340, 360. A '99 360 would be a "Magnum" engine, which I believe is the same block pattern as the earlier LA engines.

Not the same as the AMC 360 in the GW. However, your GW will have a Chrysler 727 transmission, using a case that matches the AMC engine (the A727). I presume you could swap the guts of your A727 into a Chrysler-cased 727 and it would bolt-up to the LA 360. Not a trivial change; I expect everything would have to come out of the A727 so the modified transmission and Jeep transfer case will bolt up to the new engine. The donor you are looking at now likely does not have the plain 3-speed 727 like the GW, so I'd expect you would need to find that separately.

There is a lot involved in an engine swap - new mounts, wiring, plumbing, etc. Plus the GW engine compartment may not be wide enough for this engine. Many V8s will interfere with the brake booster and/or heater box. How much time and effort are you willing to put into this? Near 100% certain fixing the engine you have, or finding another used engine, will be way faster and less expensive.

As mentioned, the small block Chevrolets are the most popular "complete" swap for these. Things are usually popular for good reason. Lots of example build threads here and at IFSJA; search.
https://www.bing.com/search?q=site%3Afs ... rolet+swap
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
Blockchain the vote.
User avatar

Yeller
Posts: 1521
Joined: Thu Apr 01, 2021 7:54 am
Location: Rogers County Oklahoma

Re: Need some help on an engine swap

Post by Yeller »

Swapping a 360 isn’t terrible but not exactly easy. You would need to find a 4x4 version of the transmission, the OD unit on the back is completely different of a 4x4. Of the fuel injection harnesses it is one of the simpler ones, it is basically a stand alone unit on its own. The issue becomes the platform was discontinued in 2002, so it’s old and you’re reliant on old technology that has very minimal suport. I’m sure there is a vehicle anti theft system that would need disabled at a minimum, the guy that I know that used to do that on the Chrysler stuff is no longer with us, so I don’t have much to help. Just because you have it or it’s cheap doesn’t always mean it’s the best candidate, there’s a reason many of us have migrated to the Chevy LS platform.
The bus I ride is so short it is a yellow Smart Car full of squirrels, monkeys and clowns.

1970 J2500 Resto Mod
https://www.fsjnetwork.com/forum/viewt ... 12&t=21395

1974 Bronco “Broncno”
https://classicbroncos.com/forums/threa ... st-3411909
User avatar

Stuka
Site Admin
Posts: 11789
Joined: Thu May 12, 2011 5:53 pm
Location: CA
Contact:

Re: Need some help on an engine swap

Post by Stuka »

What is the reason for the swap? Is the AMC engine bad? If swapping just to swap, the Cheaper 360 is not the engine I would choose. As noted above, the magnum engines have poor aftermarket support.
2017 JKU Rubicon
Pevious Jeeps: 1981 J10, 1975 Cherokee, 2008 JK, 2005 KJ, 1989 XJ

sierrablue
Posts: 1208
Joined: Wed Nov 30, 2022 8:02 pm
Location: MN/CO

Re: Need some help on an engine swap

Post by sierrablue »

The 360 out of a Dakota would really only help in terms of out of the box, it has fuel injection and a computer controlled overdrive transmission, but keep in mind you gotta wire all that up to work too.

I'd stay away from the SBC; doesn't really gain you much of anything (functionally, on a Jeep) over what you already have. The LS isn't a terrible swap; very similar to the 360 in terms of what all has to be done, BUT you can expect to walk into a parts store and they'll have the part you need. That's probably the cheapest/easiest route, depending on what you want out of it.

I'm not a huge fan of the LS myself, but I acknowledge that it definitely has its advantages over a stock obscure carb V-8 no overdrive drivetrain. Even outside of that I'd take an LS over say a Subaru engine any day, just because of reliability.

I have a friend with a 4x4 Dakota, same engine you're talking. It's got a big cam and headers and this loud obnoxious exhaust, and a tune on it, and he's getting the same mileage as me, in my 50-year-old Jeep, with a few bolt-ons on the engine, a carb, and no overdrive. And I can keep up with him off the line. I'll grant you the Buick is different than the AMC but my point is that you're not gaining anything.
'71 Wagoneer (DD)
-B350 (HEI, iron 4-barrel, Edelbrock 1406), TH400, D20
-'74 D44 front (nonpower discs)
-custom headliner
-Front shoulder belts (rears eventually)

viewtopic.php?t=23070

There are 2 major differences between new Wranglers and FSJs. FSJs are meant to be both utilitarian and capable, not just capable. FSJs are also rarely initially recognized as Jeeps by the average American.

sierrablue
Posts: 1208
Joined: Wed Nov 30, 2022 8:02 pm
Location: MN/CO

Re: Need some help on an engine swap

Post by sierrablue »

Yeller wrote: Mon May 29, 2023 7:15 am Swapping a 360 isn’t terrible but not exactly easy. You would need to find a 4x4 version of the transmission, the OD unit on the back is completely different of a 4x4. Of the fuel injection harnesses it is one of the simpler ones, it is basically a stand alone unit on its own. The issue becomes the platform was discontinued in 2002, so it’s old and you’re reliant on old technology that has very minimal suport. I’m sure there is a vehicle anti theft system that would need disabled at a minimum, the guy that I know that used to do that on the Chrysler stuff is no longer with us, so I don’t have much to help. Just because you have it or it’s cheap doesn’t always mean it’s the best candidate, there’s a reason many of us have migrated to the Chevy LS platform.
2002 is old now?! You didn't tell me I was rapidly approaching being considered "old"!!!!!!!

(for those who take everything on the web seriously, this is entirely a joke)
'71 Wagoneer (DD)
-B350 (HEI, iron 4-barrel, Edelbrock 1406), TH400, D20
-'74 D44 front (nonpower discs)
-custom headliner
-Front shoulder belts (rears eventually)

viewtopic.php?t=23070

There are 2 major differences between new Wranglers and FSJs. FSJs are meant to be both utilitarian and capable, not just capable. FSJs are also rarely initially recognized as Jeeps by the average American.
User avatar

Yeller
Posts: 1521
Joined: Thu Apr 01, 2021 7:54 am
Location: Rogers County Oklahoma

Re: Need some help on an engine swap

Post by Yeller »

sierrablue wrote: Thu Jun 01, 2023 5:17 pm

2002 is old now?! You didn't tell me I was rapidly approaching being considered "old"!!!!!!!

(for those who take everything on the web seriously, this is entirely a joke)
You’d be an antique if you were a robot🤣🤣🤣🤣🤣
The bus I ride is so short it is a yellow Smart Car full of squirrels, monkeys and clowns.

1970 J2500 Resto Mod
https://www.fsjnetwork.com/forum/viewt ... 12&t=21395

1974 Bronco “Broncno”
https://classicbroncos.com/forums/threa ... st-3411909

sierrablue
Posts: 1208
Joined: Wed Nov 30, 2022 8:02 pm
Location: MN/CO

Re: Need some help on an engine swap

Post by sierrablue »

Lol. Not just bots; bikes too--I have a relatively nice one that's an '06 but it's considered a classic like the SJ is now lol. One time I was at the mtb trail and was loading up the bikes, and one guy came up on one side of me wanting to talk about the bike and another guy came up on the other side wanting to talk about the Jeep lol.

Anyway yeah not new stuff, which the LS arguably isn't either, but they don't make computers/harnesses for them like they do for the LS, Hemi, and Coyotes. You'd have to study the wiring on the Dakota and figure out how to tie that into what you have in your SJ. Not impossible but def. a PITA.
'71 Wagoneer (DD)
-B350 (HEI, iron 4-barrel, Edelbrock 1406), TH400, D20
-'74 D44 front (nonpower discs)
-custom headliner
-Front shoulder belts (rears eventually)

viewtopic.php?t=23070

There are 2 major differences between new Wranglers and FSJs. FSJs are meant to be both utilitarian and capable, not just capable. FSJs are also rarely initially recognized as Jeeps by the average American.

SJTD
Posts: 1924
Joined: Tue May 21, 2013 12:02 pm
Location: Lompoc, Sunland or somewhere between

Re: Need some help on an engine swap

Post by SJTD »

I'd use a Ford 360. Bolts right in, right? Can't beat an FE block.
Sic friatur crustulum

'84 GW with Nissan SD33T, early Chev NV4500, 300, narrowed Ford reverse 44, narrowed Ford 60, SOA/reversed shackle in fornt, lowered mount/flipped shackle in rear.
User avatar

Stuka
Site Admin
Posts: 11789
Joined: Thu May 12, 2011 5:53 pm
Location: CA
Contact:

Re: Need some help on an engine swap

Post by Stuka »

SJTD wrote: Thu Jun 01, 2023 8:00 pm I'd use a Ford 360. Bolts right in, right? Can't beat an FE block.
Note for anybody that may come across this thread, Ford and Chrysler 360's do not bolt into FSJ's :)
2017 JKU Rubicon
Pevious Jeeps: 1981 J10, 1975 Cherokee, 2008 JK, 2005 KJ, 1989 XJ

sierrablue
Posts: 1208
Joined: Wed Nov 30, 2022 8:02 pm
Location: MN/CO

Re: Need some help on an engine swap

Post by sierrablue »

SJTD wrote: Thu Jun 01, 2023 8:00 pm I'd use a Ford 360. Bolts right in, right? Can't beat an FE block.
Why a 360 though???? If a 360 will bolt in so will a 390 or a 428...

700 lbs of pure torque :-bd
'71 Wagoneer (DD)
-B350 (HEI, iron 4-barrel, Edelbrock 1406), TH400, D20
-'74 D44 front (nonpower discs)
-custom headliner
-Front shoulder belts (rears eventually)

viewtopic.php?t=23070

There are 2 major differences between new Wranglers and FSJs. FSJs are meant to be both utilitarian and capable, not just capable. FSJs are also rarely initially recognized as Jeeps by the average American.

SJTD
Posts: 1924
Joined: Tue May 21, 2013 12:02 pm
Location: Lompoc, Sunland or somewhere between

Re: Need some help on an engine swap

Post by SJTD »

I thought we were talking 360's.
Sic friatur crustulum

'84 GW with Nissan SD33T, early Chev NV4500, 300, narrowed Ford reverse 44, narrowed Ford 60, SOA/reversed shackle in fornt, lowered mount/flipped shackle in rear.

sierrablue
Posts: 1208
Joined: Wed Nov 30, 2022 8:02 pm
Location: MN/CO

Re: Need some help on an engine swap

Post by sierrablue »

True mb.
'71 Wagoneer (DD)
-B350 (HEI, iron 4-barrel, Edelbrock 1406), TH400, D20
-'74 D44 front (nonpower discs)
-custom headliner
-Front shoulder belts (rears eventually)

viewtopic.php?t=23070

There are 2 major differences between new Wranglers and FSJs. FSJs are meant to be both utilitarian and capable, not just capable. FSJs are also rarely initially recognized as Jeeps by the average American.

Srdayflyer
Posts: 398
Joined: Mon Mar 18, 2019 2:08 pm

Re: Need some help on an engine swap

Post by Srdayflyer »

i believe i recall reading somewhere that the 390 block was either bored or stroked to come up with the 401

sierrablue
Posts: 1208
Joined: Wed Nov 30, 2022 8:02 pm
Location: MN/CO

Re: Need some help on an engine swap

Post by sierrablue »

Srdayflyer wrote: Sat Jun 03, 2023 5:34 pm i believe i recall reading somewhere that the 390 block was either bored or stroked to come up with the 401
I mean the 304/360/390/401 are all the same engine with the same intake, heads, cams and everything, with a different displacement...
'71 Wagoneer (DD)
-B350 (HEI, iron 4-barrel, Edelbrock 1406), TH400, D20
-'74 D44 front (nonpower discs)
-custom headliner
-Front shoulder belts (rears eventually)

viewtopic.php?t=23070

There are 2 major differences between new Wranglers and FSJs. FSJs are meant to be both utilitarian and capable, not just capable. FSJs are also rarely initially recognized as Jeeps by the average American.

akguy09
Posts: 301
Joined: Mon Aug 30, 2021 6:11 am
Location: Ellicott, Colorado

Re: Need some help on an engine swap

Post by akguy09 »

So I have a 401...just waiting for my 304 to stretch out
1979 Jeep J-10 304/T-18
2017 Jeep JK 2DR
2021 PowerWagon

sierrablue
Posts: 1208
Joined: Wed Nov 30, 2022 8:02 pm
Location: MN/CO

Re: Need some help on an engine swap

Post by sierrablue »

akguy09 wrote: Mon Jun 05, 2023 12:22 pm So I have a 401...just waiting for my 304 to stretch out
Lol I don't think that works. I think they did the walls on the 304s thinner or something...I wouldn't trust that.
'71 Wagoneer (DD)
-B350 (HEI, iron 4-barrel, Edelbrock 1406), TH400, D20
-'74 D44 front (nonpower discs)
-custom headliner
-Front shoulder belts (rears eventually)

viewtopic.php?t=23070

There are 2 major differences between new Wranglers and FSJs. FSJs are meant to be both utilitarian and capable, not just capable. FSJs are also rarely initially recognized as Jeeps by the average American.
User avatar

tgreese
Posts: 7118
Joined: Fri Jun 08, 2012 6:31 am
Location: Medford MA USA

Re: Need some help on an engine swap

Post by tgreese »

Gen II is the 290/343/390, same except for bore/stroke. Then came gen III the 304/360/401 had a longer stroke with better heads as I understand it. Same bell pattern AFAIK, maybe different deck heights gen II to gen III or something else similarly esoteric (change in deck height is suggested by a longer stroke). IIRC gen III has better heads with the 'dog leg' ports.

The 390 and 401 have their own steel crank and rods IIRC. A 360 is a bored-out 304; same cast crank and rods. The 304 heads have smaller valves to clear the smaller bore diameter. When they cast the blocks, they use different cores depending on the displacement. The 304 starts out with about the same cylinder wall thickness as the 360. You can't just bore out a 304 to 360 or such - the walls will be too thin. You can sleeve a block with enough web thickness to get a much larger bore but it's about $100/hole, maybe more now.

Guys, the OP hasn't been on since May 30, so we're just talking to ourselves here.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
Blockchain the vote.
Post Reply