258 ID help

[amc75matador]

wondering if anyone can help ID a AMC 258 i6 / 4.2l engine in my 84 CJ7 . I know the engine is not original to this Jeep as it has a steel valve cover, the following numbers are on the block by the distributor just below the deck surface: 802A27. I know there is a way to decipher these numbers but I dont know how, can anyone tell?

 

[danc9]

Will this help?

AMC 258 CID (4.2 Litte) Engine Block Identification Numbers - Eaglepedia

 

[amc75matador]

Example: 3 10 C 11
1st Number Character is the build year: 3 = 1983, 4 = 1984
2nd and 3rd Number Characters is the build month: 01 = January, 12 = December
4th Letter Character code indicates the engine: C = AMC 258 i6 / 4.2l CID / 2v Carburetor / 9.2:1 Compression Ratio
5th and 6th Number Characters is the build day: 01, 02, 03 up to 31.
The example code 3 10 C 11 translate to: AMC 258 i6 / 4.2l CID (AMC 258 i6 / 4.2l Liter) engine with 2V Carburetor and a 9.2:1 Compression Ratio, built on October 11, 1983.

So according to this mine is built in feb 27th 1978, but what is the "A"? I am guessing not a AMC 258 i6 / 4.2l ? maybe AMC 232 i6 ?

 

[danc9]

And another...

http://street2mud.com/webfiles/AMC Engine codes.pdf

clear as mud??? A I believe is 1bbl AMC 258 i6 / 4.2l (71-79)

 

[amc75matador]

And another...

http://street2mud.com/webfiles/AMC Engine codes.pdf

clear as mud??? A I believe is 1bbl AMC 258 i6 / 4.2l (71-79)

So according to this my engine is a 75 engine

thanks