torque numbers differ from books
 

I got a new book, how to build and modify p 911 engines from mr. Dempsey and noticed something strange. All of his torque numbers differ from mr. Andersons book. For example a 930-20 84-96 3.2 is rated at 209 ft pounds in anderson book and 284 ft in dempseys book. What am I missing?

Almost any printed matter can and will have errors, including factory docs
factory spec for 930/20 has the correct NM but incorrect lb-ft

correct
net torque to SAE J 1349 205 ft-lbs@4800 = 278 NM
net torque to DIN 70020 284NM = 209lb-ft

so printing or translation error or just using a different measuring standard can all contribute