Our original composite gasket has been updated to this TEN111 version. The original would accommodate a piston size 79-80mm. This bore size is seldom used except on race cars. The gasket bore size has been reduced to 78mm. Usual maximum bore size is 77.5mm and as such the gasket now adds increased reliability to the small land between each pair of bores.
Oil seepage from the length of the TR5/6 head gasket along the push rod side has always been an irritation. The oil usually runs to the rear, drops onto the gearbox bell housing and then on to the floor. It has proved very difficult to prevent this leak as the major head stud clamping is well inboard of the slim outer gasket edge. To overcome this issue we have introduced a neoprene sealing track round the outer circumference of the whole gasket. This will effectively contain all oil within this unbroken neoprene track. As fitted to all our standard, fast road & race engines
0.040" (1mm) thick when compressed.