The home of the UK's greatest sportscar
14/11/2008
Racing Green TVR can now offer an uprated bearing for the half time sprocket. The half time bearing on the TVR Speed 6 has been known as a potential problem largely due to loads imposed on it by the requirement to run the timing chains tight. Due to the clearance between the cam cover and the upper timing chain being minimal there is a tendency to over tighten the upper chain during servicing to ensure that the engine runs quietly. If this adjustment is done incorrectly or when the engine is cold then when the engine is fully hot the expansion of the all aluminium cylinder head and block places huge loads on both the upper and lower timing chain and the half time bearings. Whilst the half time bearings are generally ok any increased loads can have adverse affects causing the bearing to become noisy and/or fail. The standard bearing, TVR E6326, is a single race ball bearing and although the half time sprocket uses 2 of these bearings an uprated version should be considered. The uprated bearing offered by Racing Green TVR, TVR E6326 RG, is a dual race bearing with significantly higher dynamic and static load ratings but with very similar dimensions. The internal and external diameters are the same but the depth is 4mm greater which means that the half time sprocket does require minor machining for these bearings to fit. The uprated bearing, TVR E6326 RG, has over 30% increased dynamic load rating and is an almost 50% increase in static load rating so is significantly more capable. Customers interested in this bearing should also look at the Latest News article on the Racing Green TVR timing chain upgrade in the link below.