What is the manufacture octane requirement for 1983 280zx non turbo? 87, 91 or 93?

 

I use 87 in my N/A 1983 280ZX as recommended by the owner's manual page 116. You can find an online owners manual at http://www.xenonzcar.com/s130/owners.php

 

Imho, the octane can be 87 or 91 IF the fuel has no ethanol in it. The owner’s manual says 87 and all, but my experienced mechanic stresses to me that it should be ethanol free bc ethanol gas was not available at that time (1983) and it can be rough on the seals. I have two ZXs (‘80 AE and an ‘83…..both NA non turbo) and did drive each w ethanol gas wo issue, but have since switched to ethanol free gas unless I can’t find any atm I need to fill up.