I just bought a 77 208z that came with a spare motor and trans from a 81 280z. I was planning on rebuilding one of the motors for scca/ autox and was wondering what are the different engine codes and what are the specs on the motors?

Thanks!

First off the '81 is a ZX block. Same displacement but if from a NA car it has flat topped pistons . Unlike your '77 block. The head will either be a P-90 or 90a if a turbo engine or a P-79 if NA . This is the last evolution in development of these in-line engines. The casting of the ZX F-54 block is different in that the water jackets are different . Supposedly making the block stronger. I don't know if this true as I have only read this info. I am running a '82 ZX in my 240 with SUs and am vary happy with the change. Also the later heads have the preferred shaped combustion chambers. The exhaust ports on the 90 head are square and the 79 , diamond shaped. With .030'' off the 79 head gave me 9.4 to 1 compression. Not that high but I can still run mid or regular fuel. Gary Hope this helps.