I've no idea where the misinformation of a 240bhp 911SC came from but as this is the SC forum the facts are as most people know.
In 1978 the first SC was built with a 180bhp engine - almost identical to the previous Carrera 3.0 but detuned so it didn't outrun the 928! According to factory sources and indeed mentioned in Paul Frere's '911 Story' most engines regularly achieved 190 bhp on the factory dino's. MY 1980 were credited with 188bhp despite the only change being an increase in compression ratio to 8.6:1 up from 8.5:1. Observers have stated that the increasingly stringent governmental requirements for exact figures to be released forced Porsche to merely give a 'revised' set of figures for the MY 1980 engine. 1981 saw the first real increase in performance to 204bhp and this was the most stock factory cars ever produced. The 3.1 ltr 'Weissach specials' - not to be confused with the Weissach limited edition model - had a bhp figure in the region of 215-230 bhp depending on who you speak to, there were about a 100 made some people may own them but never know it.
Finally in 1984 Porsche constructed the Championship winning Type 954 911 SCRS there are 4 of the 5 'werks' cars still in existence all achieve 290bhp with a race exhaust and 935 Kugelfisher injection. Fifteen homologation road going 911 SCRS s were made each with 255bhp again using Kugelfisher injection but with a road going exhaust. If you find one of these let me know, I want it!
Hope that sets the figures arguement straight.