Its just a matter of knowing where to look.
Ok go to
www.faa.gov and search for type certificates (Tc's)
Then do a search by make and engines, you will then get all the detailed information held on all engines used in the USA you will get everything you need to know from whats on it etc to the weights, performance and everything needed to operate it.......
saving you some time the O-320 one is here
http://rgl.faa.gov/Regulatory_and_Gu...FILE/E-274.pdf
The Teledyne Continental O-200 is here
http://rgl.faa.gov/Regulatory_and_Gu...FILE/E-252.pdf
Finally the O-235 one is here
http://rgl.faa.gov/Regulatory_and_Gu...FILE/E-223.pdf