Swap to AMC V8 or to 3.4 Chev or Firebird?

[Melmoe]

Thanks for letting me join this awesome Forum! 
 

 I recently purchased a 1986 Commanche 4x4. It has a original factor replacement 2.8 in it with about 20,000 on it. The trans is having issues on the truck. 

  My question about the Jeep is do I replace the engine with a 3.4 from the wrecking yard and rebuild the trans or……….. I have a AMC 360 - 350 hp that was recently built that has a recently built 904 trans. I have no car that I need to put the 360 in. Do I use this combination in the truck after changing the trans tail shaft or use the 3.4 engine. What changes would I have to make to install the 360 or a 3.4? 

[Pete M]

the 3.4L block will go right in and make use of all the 2.8's accessories/intake/exhaust.  if the 2.8L is in good shape, you can leave it too and just focus on the trans.    there's a good thread on the 3.4 swap in the link in my signature.

 

the 360 will need a different all-the-things-everywhere. 

[derf]

The 360 is a physically large engine.  You can make it fit but it will take a lot of custom work.   And nobody makes any swap kits that will help.

 

I'd go with a 3.4 from a GM F body (Camaro/Firebird).  Grab the whole wiring harness with the engine and it's a straightforward swap.  If the donor has the 4L60 automatic, I'd keep that as well.  Easy to adapt it to the Jeep t-case (or just run it as 2wd if that's what you have).  That way you get a pretty good overdrive.

[watchamakalit]

6 hours ago, derf said:

The 360 is a physically large engine.  You can make it fit but it will take a lot of custom work.   And nobody makes any swap kits that will help.

 

I'd go with a 3.4 from a GM F body (Camaro/Firebird).  Grab the whole wiring harness with the engine and it's a straightforward swap.  If the donor has the 4L60 automatic, I'd keep that as well.  Easy to adapt it to the Jeep t-case (or just run it as 2wd if that's what you have).  That way you get a pretty good overdrive.

 

Or if you really want the V8 I'd suggest an ls swap. 

[The86manche]

It might be an endeavor but I'd say slap that 360 in. 

When 2.8 dies I plan to put a an amc engine in mine. 304/360/ or the rare 401 if I can find one. 

[derf]

2 hours ago, The86manche said:

It might be an endeavor but I'd say slap that 360 in. 

When 2.8 dies I plan to put a an amc engine in mine. 304/360/ or the rare 401 if I can find one. 

It's getting harder and harder to find parts for an AMC V8.  And the 401 doesn't take an overbore very well.  I'd focus on the 360 if I was going to swap in an AMC these days.

 

Though I'm much more likely to take out an AMC and replace it with a GM or Ford V8.  Those are a lot easier to find parts for.  That would be my plan if I go back to full size Jeeps.

[bruceb]

Here is a interesting article to get more power from a 3.4 with head swap from Pontiac 3400.  http://www.ls1.com/forums/f68/some-insight-into-3-4l-ohv-motor-4706/

[The86manche]

1 hour ago, derf said:

It's getting harder and harder to find parts for an AMC V8.  And the 401 doesn't take an overbore very well.  I'd focus on the 360 if I was going to swap in an AMC these days.

 

Though I'm much more likely to take out an AMC and replace it with a GM or Ford V8.  Those are a lot easier to find parts for.  That would be my plan if I go back to full size Jeeps.

That is slightly true. Blocks and parts are still a plenty around me here on the east coast. Maybe not a 401, those are harder to find. There was a guy with a stash of 401 blocks out in New York but he wanted around 5k for everything.. which is still a lot of money for just motors..

And if I could help it, I'd definitely try to avoid boring out any engine I put in it.

I just like the idea of putting an amc heart in an amc vehicle.