Hey, I recently bought a n "88 vert. Is there anyway to tell if the engine is an original or newer (rebuilt). Appreciate your help, thanks.

 

It's an NA so odds are that it is original. IF you see any markings on the rotorhousings that could indicate a rebuild or a junkyard replacement. Also if you see any paint on any of the block then it is quite possibly a rebuild. Mazda remans often paint the front cover and rotorhousings in this chrome-like aluminum paint, and also usually have a blue tag on the front cover...and sometimes even a mazda part number sticker on the oil filler tube or oilpan, however that often gets removed.