My 5/70, with original engine: '2400' valve cover = yes 'Warm/cold flap' on the air cleaner snorkle = noalso 'no' re warm-air-delivery flex hose, and 'no' re the matching shroud plate mounted around the bottom of the exhaust manifold (has a 'spigot' where the flex hose attaches) Back in the day, I owned a 72 Z as a daily driver. On really cold Canadian mornings in January or February (days that were much colder than I expect Skinner-Union ever imagined) the cold-start drill consisted of: Choke to 'full'open hoodset warm-air flap to 'warm' position3-second shot of ether into the air cleanerset warm-air flap back to 'cold'close hoodstart engine