4.0L head on 4.2L block - JeepForum.com
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Unread 05-26-2003, 07:00 PM   #1
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1984 CJ7 
Join Date: Apr 2003
Location: Tampa, FL
Posts: 116
4.0L head on 4.2L block

Anyone done the 4.0L head conversion on their 258? What were the results? Was it worth it? Was filling the water jacket holes a pain in the butt?

My 258 is shot and in need of replacement. I want to keep the 6 cyl but looking for more muscle.

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Unread 05-26-2003, 10:41 PM   #2
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1982 CJ8 
Join Date: Apr 2001
Location: Near Fairfield, CT
Posts: 1,210
It's great to ask questions, I would say they are the main reason for a forum like this. That being said, try a search here, Google, and also jeepsunlimited.com is a good place. This has been discussed many, many times, and the web has several articles on it.

I will be doing this swao towards the end of the summer.

Good luck
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Unread 05-27-2003, 09:52 PM   #3
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here are some links for you:



I wouldn't waste my time and money doing this swap on an engine in need of a rebuild though.
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