Once upon a time, these folks published the "TUNING MANUAL FOR STANDARD TRIUMPH CARS PRODUCED BETWEEN 1959 & 1980" by G.H. Thomas. It goes through various levels of tuning from fast road to full race for most models. Also, there is much more supportive information included than in Kastner's sometimes optimistic publication. I managed to find a copy of this from Chris Witor.
Got an update? This does NOT mail to the vendor!The Monster List of British Vendors is brought to you by The Dimebank Garage