1969 Javelin Engine Swap

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   Hello,I have been reading posts on this forum for years, but finally posting for the first time.
My father and I are currently working on two different AMC projects. I will ask about my Gremlin in a separate post.
His 69 Javelin has a newly rebuilt 290 and automatic transmission. Ultimately he would like more power; like to be able to drive it around town, drive it to the strip about 30 miles away, take it down the track, and drive it home. He likes the idea of a 360 or 401 with the edelbrock EFI conversion in the long run.
Tomorrow, we are going to look at a 72 Jeep J4000 with a 360. Would this be a vehicle to try to swap engines and/or transmissions and then resell the Jeep?
Thanks

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Drooque Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Jun/29/2020 Location: Montana Status: Offline Points: 33	Post Options Post Reply Quote Drooque Report Post Thanks(0) Quote Reply Topic: 1969 Javelin Engine Swap Posted: Jun/29/2020 at 10:07pm
	Hello, I have been reading posts on this forum for years, but finally posting for the first time. My father and I are currently working on two different AMC projects. I will ask about my Gremlin in a separate post. His 69 Javelin has a newly rebuilt 290 and automatic transmission. Ultimately he would like more power; like to be able to drive it around town, drive it to the strip about 30 miles away, take it down the track, and drive it home. He likes the idea of a 360 or 401 with the edelbrock EFI conversion in the long run. Tomorrow, we are going to look at a 72 Jeep J4000 with a 360. Would this be a vehicle to try to swap engines and/or transmissions and then resell the Jeep? Thanks

1970390amx Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jul/11/2008 Location: colorado Status: Offline Points: 3314	Post Options Post Reply Quote 1970390amx Report Post Thanks(1) Quote Reply Posted: Jun/29/2020 at 11:00pm
	71 and older V8 engines have a different crankshaft flange. Unless both vehicles have manual transmissions trying to swap outside of the correct year set is very difficult. 72 and newer engines in jeeps untell about 1980 used a turbo 400, while cars used a torqueflite. Some a 727 or 904 type automatic. Just my 2 cents but you would be better off just buying a 360 and a 727 and rebuilding both.
	1970 390 4speed Bittersweet shadow mask AMX 1970 Amx missing most everything, or in a box

Drooque Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Jun/29/2020 Location: Montana Status: Offline Points: 33	Post Options Post Reply Quote Drooque Report Post Thanks(0) Quote Reply Posted: Jun/30/2020 at 11:06am
	Thank You, 1. What about the 290 in the Jeep? I have gathered from reading posts that the Gen 2 engines can bolt to newer trans with a spacer/adapter. 2. What about the 360 from the Jeep in the Javelin with a different 2wd TH400? We happen to have a freshly rebuilt TH400 that was bolted to a SBC. I know there are adapters for the different bell housing bolt patterns between the different TH400. Ideally we would like to go from 2 running vehicles to 2 running vehicles, so we can sell the donor and recoup our costs and start saving for the Edelbrock EFI.

Heavy 488 Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Apr/27/2019 Location: In the Status: Offline Points: 3553	Post Options Post Reply Quote Heavy 488 Report Post Thanks(1) Quote Reply Posted: Jun/30/2020 at 11:18am
	The crank adapter you need to put the 290 in the truck isn't available. Then there's a flywheel balance issue. These aren't SBC's.

Mopar_guy Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Joined: Jun/07/2009 Location: Ohio Status: Offline Points: 4823	Post Options Post Reply Quote Mopar_guy Report Post Thanks(1) Quote Reply Posted: Jun/30/2020 at 11:40am
	I don't see how you can pull this off since you're crossing the 71 crank flange boundary. To do the swap you want to do you need to find a 71 360 donor vehicle in order to put the 290 back into and bolt up. Besides that, buying adapters to do what you want gets expensive. It's a good idea in theory but it's not just an easy swap as you thought.
	"Hemilina" My 1973, 5.7 Hemi swapped Javelin

mramc Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jul/12/2007 Location: United States Status: Offline Points: 3219	Post Options Post Reply Quote mramc Report Post Thanks(0) Quote Reply Posted: Jun/30/2020 at 5:18pm
	Check out the NOVAK transmission adopter web site. They have a full knowledge based web site section on engine transmission swaps. They specialize in Jeep , but it all applies to the AMC cars also. The Novak adopter web site will pretty much answer all your questions and tell you what you can and can not do. And you can do just about any thing, all it takes is cash. LRDaum
	LRDaum

1982AMCConcord Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jul/13/2012 Location: Kenosha, WI Status: Offline Points: 1287	Post Options Post Reply Quote 1982AMCConcord Report Post Thanks(1) Quote Reply Posted: Jun/30/2020 at 8:03pm
	Ah... you could use this early 304 crank in a later 360 block and get a nice 360. It's on Facebook...

Drooque Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Jun/29/2020 Location: Montana Status: Offline Points: 33	Post Options Post Reply Quote Drooque Report Post Thanks(0) Quote Reply Posted: Jun/30/2020 at 8:07pm
	Thanks to everyone that responded. It looks like the issue isn't if it can be done, but more the cost of the adapter if you can even find one any more. We looked at the Jeep today and it is awesome. The 360 is recently rebuilt with a performance cam, head work, edelbrock intake and carb, headers, etc. It moves real nice. I really want to justify putting the engine in the Javelin. I might bring the diagram and pictures of the adapters I found on this forum to the machine shop and ask them what they could do. Otherwise, I might look around for a different engine for the jeep. I have a 258 I would put into it, but I don't think it would be powerful enough.

bigbad69 Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Joined: Jul/02/2007 Location: Ottawa, Ont. Status: Offline Points: 6670	Post Options Post Reply Quote bigbad69 Report Post Thanks(1) Quote Reply Posted: Jul/01/2020 at 9:17am
	That Jeep sounds like a keeper as is. Rather than tear it apart, why not source a 360 with an early crank, or a 343, to drop in the Javelin? It would be a bolt-in solution. The money you save on adapters could go into the engine. Depending on your budget, you could go 390/early 401, but you will pay a lot more for those engines.
	69 Javelin SST BBO 390 T10

1970390amx Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jul/11/2008 Location: colorado Status: Offline Points: 3314	Post Options Post Reply Quote 1970390amx Report Post Thanks(1) Quote Reply Posted: Jul/01/2020 at 2:00pm
	In my opinion swapping to a different engine will do damage to the relatively week trans that is behind the 290. If you need a stronger trans any upgraded engine should come with an upgraded transmission
	1970 390 4speed Bittersweet shadow mask AMX 1970 Amx missing most everything, or in a box