73 Block to an 83 Head???

Hi Guys,

New to your form, hope to have many hours of enjoyment ahead! I've got a question for the serious CJ5 Gear Head.

I've got a 1973, 258 straight six that I'd like to put a 1983 Head on. I know the spark plugs will probably be different and probably the push rods too, but is there anything else I need to be concerned about if I go ahead and mate the 73 engine to the 83 head??? Thx for the help!!!

 

what's the reason for the 83 head?

IIRC there wasnt alot of variation with the 258 heads.

 

The valve covers are different and the head bolts are 7/16in vs. 1/2in on the 73 block other than that the rest is the same. If you need a new head a 4.0L head is a good upgrade and has the right size head bolts.

 

Thanks for the replies DrDanteIII and 73cj5!!!

DrDanteIII - The reason for the switch is because the 73 head is cracked and I just happen to have an 83 at hand (a friend). Also, money is an issue and a free head from a friend is worth a lot to me right now.

73cj5 - The head bolts and valve covers being different I can live with. I just wanted to make sure there was nothing "major" I needed to consider. Also, I've been reading about the 4.0L head swap. It does sound good and maybe in the future when I've got more cash to spend I'll do that upgrade.

I really appreciate you guys helping me out!!!

Sincerely,
-The Cactus Kid (aka Dave)

 

I swapped a '74 head out with an '86 head when I did my cam and lifter replacements. Something I would like to pass along is the combustion chambers were smaller on the later model head and the pistons were concave. The push rods were longer for the newer head. My engine has flat top pistons and I didn't have any trouble with valve clearance but I thought it would be something you might want to be aware of.