Author Topic: 4.2 to a 4.0 swap  (Read 1143 times)

0 Members and 1 Guest are viewing this topic.

Offline beej8508

  • Eagle
  • **
  • Posts: 30
  • Thumbs Up 9
4.2 to a 4.0 swap
« on: February 19, 2012, 06:55:52 PM »

The engine in my Eagle is in need of a rebuild.  So, I have been looking for a used engine.

I found an engine from a 1988 Jeep with very low miles that is inexpensive and runs/sounds good.

How difficult is this going to swap out?  I am by no means a mechanic, but I have a friend (mechanic) who will be doing the swap.

I would really like to keep it carbed if possible. 
1981 Eagle Kammback
1983 Eagle Sport Wagon
1972 AMC Javelin SST
1924 Model T Ford Speedster
1970 Mercury Cougar (Special Edition)

Offline doc65

  • Eagle DL
  • ***
  • Posts: 252
  • Thumbs Up 6
  • Ogden, UT
Re: 4.2 to a 4.0 swap
« Reply #1 on: February 19, 2012, 07:25:22 PM »
It's doable, but an 88 will be the Old Renault/Bendix (RENIX) injection system.  Not near as clean as the 91-95 ChryCo HO setup.  You could however put your 258 carb manifold on it and use an electric fuel pump to feed it and have a Carb'd 4.0 also there is the 83 SX4 that's available in the spokane are that is a 258.

Offline beej8508

  • Eagle
  • **
  • Posts: 30
  • Thumbs Up 9
Re: 4.2 to a 4.0 swap
« Reply #2 on: February 19, 2012, 07:33:14 PM »
Is that the SX4 down near Yakima...bad tranny..

I have thought about giving the guy a call...but have run out of parking space.  :)

I am glad to hear that I can use my carb and manifold on it...the carb is a rebuilt and so far am not having any problems with it!

Thanks
1981 Eagle Kammback
1983 Eagle Sport Wagon
1972 AMC Javelin SST
1924 Model T Ford Speedster
1970 Mercury Cougar (Special Edition)

Offline mudkicker715

  • Moderators
  • AMC Eagle Nest Addicted
  • *****
  • Posts: 1800
  • Thumbs Up 45
Re: 4.2 to a 4.0 swap
« Reply #3 on: February 19, 2012, 08:02:33 PM »
I use a carb on my stroker. so same basic thing as a 4.0

Current amc's
82 concord waggy 258 DD
84 eagle sedan stroker DD
86 eagle wagon sas 304 v8 toy
87 eagle wagon stroker

Manitowoc WI

Offline doc65

  • Eagle DL
  • ***
  • Posts: 252
  • Thumbs Up 6
  • Ogden, UT
Re: 4.2 to a 4.0 swap
« Reply #4 on: February 19, 2012, 08:17:16 PM »
No, I looked at that ad on c-list too, but this is in Spokane the guy's name on here is KevinCoughlin and I saw where he recently listed it on the Feebies area.  I was going to pull it back here to Utah, but between the grade over the pass(s) toward the east & the snow I ran into on the way there I just kinda chickened out, was afraid that much weight along with a trailer on snow & ICE might not be a very good mix.  So I basically wasted a bunch of gas & the  trailer rental, but no injuries or fatalities so I sill think it was the right choice to make AT THE TIME.  In retrospect and knowing that the 4"-6"snow melted off QUICKLY, I would have been fine. 

Doc

Offline BenM

  • Eagle Turbo Diesel
  • *******
  • Posts: 1379
  • Thumbs Up 66
  • Pittsburgh, PA
Re: 4.2 to a 4.0 swap
« Reply #5 on: February 20, 2012, 12:22:13 PM »

The engine in my Eagle is in need of a rebuild.  So, I have been looking for a used engine.

I found an engine from a 1988 Jeep with very low miles that is inexpensive and runs/sounds good.

How difficult is this going to swap out?  I am by no means a mechanic, but I have a friend (mechanic) who will be doing the swap.

I would really like to keep it carbed if possible. 

I've done a couple 258-258 swaps. With a friend and an engine lift it was a weekend job for me.

For a 4.0, do a search for the exhaust routing, that's the biggest thing that will need fabbed up. There may be a few holes you need to tap for the front axle mounting.

You can go with the 2bbl intake you already have. It may need adjusted to line up on the newer head, I can't remember on the non HO heads. Get an electric fuel pump.

You want to swap over the distributor. If you need to keep the Eagle ECM it shouldn't know anything is different, it's just a 6 with a carb. Make sure you have both flex plates available for fitment, they are slightly different, but the 998 doesn't care too much.
NSS#47184

1987 AMC Eagle Sedan -- 1976 Pacer Coupe -- 1968 Pontiac Tempest Custom S -- 1940 Mercury (& a 2002 Jetta Turbodiesel, 5 spd., the Wife's Daily Driver)

 

Alright, finally tackling my 4.0 head swap.

Started by NoCoEagle

Replies: 28
Views: 3786
Last post February 09, 2012, 06:25:03 PM
by NoCoEagle
My Engine Swap (Picture Heavy)

Started by TLC87Eagle

Replies: 8
Views: 2749
Last post July 10, 2011, 10:17:43 PM
by Sunny
1980 Cedan Head Swap

Started by Cole1986

Replies: 4
Views: 1610
Last post April 10, 2013, 12:28:43 AM
by carnuck
several 4.0 head swap questions

Started by kajsdf

Replies: 20
Views: 7267
Last post June 11, 2013, 08:48:45 PM
by vangremlin
4.0 head swap questions

Started by EagleJoe93

Replies: 12
Views: 1790
Last post July 08, 2012, 11:46:44 PM
by carnuck