My Cobra has a 408 Clevor that my brother built in 1993. I like it - it perfroms well and looks more like a big block.
The Cleveland forum mention earlier is a great place for Clevor info. This thread talks about the head coolant mods as gaskets:
http://www.network54.com/Forum/11941...5269/IMPORTANT
I just uploaded a magazine article from 1992 on building a Clevor, which my brother used for this motor.
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