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1979 258 engine VS 1984 258 engine-Difference ?

Whats the difference between 1979 AMC 258 i6 / 4.2l engine and 1984 AMC 258 i6 / 4.2l engine. In a CJ7

The 1984 engine has more emissions control equipment. The Carter BBD carb was computer controlled and also the distributor timing. The motor made slightly less horsepower. Some motors typically in California had serpentine belts with reverse rotation water pumps. The 1979 engine also did not have a catalytic converter.
 
Just to clarify, all 79's came with catalytic converter including FSJ. The 6 cyl and 8 cyl used a pellet type while CA used a monolithic and pellet catalytic converter.
The 84 had slightly more torque and HP then the 79 engine as well.


 
The 79s crank shaft had more counter weights also to give it more rotational torque. In 82 they lightened the crank.

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Thanks for the reply's. I guess the main reason Im asking about if there are any differences is because I am rebuilding all parts of my 79 engine and with some of the parts ordered doesn't always included my year. So would parts like bearings and lifters be the same on a 1984 AMC 258 i6 / 4.2l CJ7 engine ?
 

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