A torch ignition type internal combustion engine has an auxiliary combustion chamber connected by a torch passage to a compact main combustion chamber. A cavity in the cylinder head forming a part of the main combustion chamber is provided with two intake valves on one side of the cavity and one exhaust valve on the other side. A large squish area is formed between the upper surface of the piston and the lower surface of the cylinder head and one or more suction conduits connect this squish area to the torch passage between its ends. Two torch passages may be provided; one may extend into the cavity near the exhaust valve and the other into the cavity near the remote intake valve. A plug chamber receives the spark plug electrodes and this chamber is in communication with both the auxiliary combustion chamber and the torch passage. In one form of the invention one torch passage extends from the lower end of the auxiliary combustion chamber and the other torch passage extends from the plug chamber.