HOME and how to join Forum Open Area General Scott topics engine numbers Re: Re: engine numbers

#13704
BRIAN MARSHALL
Participant

Hi Eric,
I have never seen ZP stamped on an engine and have no idea what it could stand for, although Z as a prefix rather than as a suffix, normally means 498cc, and Y as a suffix means 596 cc. Similarly P as a suffix means a ‘Powerplus’ longstroke. The 5 13/16 stamped on an angled flat on the top of a blind-head barrel is just the compression height, in inches.
Brian