Austin Mini Head Unleaded 25cc Chamber Size For 1380cc

35.6 x 29.3mm valves in chrome stem with cast iron valve guides. This specification of cylinder head, based on used core castings, is modified in true Road sport style to maximise on-road performance for those wanting maximised drive-ability when used with mild to fast-road camshaft specifications. That means optimised torque out-put through port shape and dimension development and valve throat shapes developed to work with the aforementioned camshaft types, along with suitable compression ratios given modern lead-free fuel specifications. Genuine Rover copper-beryllium lead-free exhaust seat inserts are fitted. High quality cast iron guides are used along with the latest specification chrome stemmed standard MG Metro valves (35.7mm inlet and 29.3mm exhaust) and 180lb (nominal at maximum valve lift) double valve springs to give a cylinder head capable of withstanding a maximum continual peak rpm limit of 6,500rpm and 0.475" valve lift. Combustion chambers are set at an average 24 to 25cc for big-bore engine use (1360, 1380 & 1400cc). 9-stud fitting as standard. This head has the heater take-off port open and a by-pass hose adapter fitted, both of which can be blanked off for use for 1992-on applications.