Our 1956 plus 4 with the TR engine has had a number of good worthwhile upgrades
Narrow belt conversion
Alternator conversion
High flow water pump
Tuned exhaust manifold and wrapped with lava rock wrap (keeps under bonnet temps down)
Spin on oil filter
Heat insulated fuel lines (stops vapour lock in hot weather)
Heat sheild betwen exhaust and carbs (Prevents vapour lock increases performance)
A Si Fab Aluminium rad with high flow elec fan
High port later TR4 head for better gas flow
IMG_6688 by
Robert & Ali Davies, on Flickr
and here i'm checking for sticking valves and general initial turn over. with plugs removed...
MOV_0348 by
Robert & Ali Davies, on Flickr