I just got one of those Supercharger kits. They were also sold by Sims and Rohm. They made less HP than a Turbo (my old Mr Turbo made 234RWHP on pump gas) but they make HP from idle. I just spoke to Billy Rohm about them and he stated that 210 RWHP is about average on a 1127 and a little more on a bigger bore. Mine is for the 88 Streetfighter, But now that its apart it will take me forever to get it back on the road.