I own the gregorys victa manual among others

http://cgi.ebay.com.au/GREGORYS-VIC...=item335493ceea&_trksid=p3286.c0.m14

Lots of great info, I still read it sometimes to catch up on things.

other books I have are

Gregorys small engines manual

scienific publications rover rotary mowers.

Pretty much covers most engines for me, the small engines manual even covers things like the 170 and 85cc victa engines.