Bronze flywheel for Triumph racing engine 
(See progress on this engine)
Workshop with Triumph and Ariel Square Four Engines being re-built
Rare 600 c.c. Square Four Push Rod Engine
Square Four Push Rod Engine
Square Four 600 c.c. Push Rod Engine and Case
1930 500 c.c. OHC Square Four Engine
Square Four Mark II Engine
750
c.c. Stroker Engine built by A. J. Lewis
Porting and Polishing a BSA head
Cutaway picture of Square Four Engine - Below same engine from the article in the October 1951 issue of Cycle magazine.
Engines Part II - Triumph Racing Engine
