Originally Posted by IMSA_Racing_Fan
1980s was the era of the engineering acronym marketing fads.
GSX-R (am guessing) Grand Sport eXperimental - Race
Which came with
TSCC - Twin Swirl Combustion Chamber
As far is know, GS = four cylinder inline, x = 4 Valves per cylinder, R = Racing / Sports Modell.
The same system applies to the other japanese brands, like Honda with CB = four cylinder inline, Kawaskai Z = 4 cylinder inline and so on....
If you go back in modell history, the "X" allways marks the switch to 4 valves per cylinder.