i just bought a 1990 ss454 pickup, to haul my cars around with a little style. i have noticed that in 1992 the factory horsepower rating for this truck went up considerably. does anyone know how? i cant imagine the shortblock changing and would also be suprised if its the heads.i am thinking camshaft? throttle body? maybe just ecm calibrations? i havent been able to find this info anywhere.  

The only Info I've found is the 91 received new intake valves. Probably Larger.
http://www.454ss.com/Articles_new/ENGINE.asp
Welcome  

Thats a bit newer than the BBC's I like,but a in Jan. 2000' I met a guy who had a 90'or 91'shortbed SS454,he wanted the 92'or newer 454 cause of the new cam and higher comp.it had. Never looked into that myself,but it might help you.