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MGB MGB Head Interchange

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bcliff

bcliff

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Will a Head from a 69 18GK Motor work on an early 74 18V motor?
Bruce
 
No not really, there could be two different heads on your 74 engine the 12H 2389 (big intake valve head), or the Cam1106 head, both those heads require exhaust valve cut-outs in the block, also if you have the cam 1106 the oil feed will be offset and not inline and would require a different rear rocker pedestal. Now mind you any of this can be made to worked out, but it's not a simply bolt on, plus depending on what pistons you have, they are differences in combustion chamber volumes and depth that caould result in compression ratio changes.
 
Hap's correct - you can only interchange the heads if you have the proper rocker pedestal & can carry out the necessary machine work.
 
Looks like I didn't provide enough detail. I have a 74 block. I have a complete 69 head, with rockers. I also have the 74 head, with rockers. I was wondering if the complete 69 head, with rockers will go on the 74 block.
Bruce
 
The real problem is if you were going the other way: early block, later head. As Hap said, the exhaust valves would "tick" the block. I *think* you should be okay.
 
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