just bought a 85 300zx na with a seized engine, i'm looking to get a used engine from a junk yard but wanted to know if an engine from an 87 to 89 300zx will bolt up to my 5 speed manual transmission on my 85? and will the engine be a direct fit?

 

Yes, any Z31 (84-89) NA engine should bolt right up with little problem. If you get a turbo engine, there are other parts you need to turbo a Z31, but that is doable too. All you need are the turbo specific parts of a turbo junk and they bolt right on the NA.

This web site has all you need about the differences between model years and NA vs Turbo.

ZBUM's New Nissan Z31 300ZX Homepage

this web site has all you need to know to turbo your NA.

TURBO TURBO TURBO