Racing Green TVR News

Racing Green TVR has developed a high performance cylinder head stud kit for the TVR Speed 6 engine. This is a full set of 14 studs, nuts and washers to replace the standard head bolts securing the cylinder head. The set includes 2 longer studs to be used in the dowel locating holes to ensure all the available threads in the engine block are fully utilised. These studs are the perfect length for the TVR Speed 6 cylinder application however minor variations in head machining may mean that the washers on the inlet side of the head may require slight modification. Made by ARP and using a premium grade 8740 alloy that is rated far superior to "aircraft" quality and precisely heat treated to 190,000psi. Following the heat treatment, each stud is centre-less ground to make it as close to perfectly concentric as possible, ARP studs are thread rolled after heat treatment, which gives them about 1,000% better fatigue strength than those studs that are threaded prior to heat treating. Because of the thread pitch difference between the original head bolts and these studs the original tightening torque has to be reduced otherwise the clamping loads generated are too high. Utilising this stud set is a better engineering solution for securing the cylinder head and ensuring the head gasket is correctly loaded. The original TVR solution uses cap headed coarse threaded bolts and this is not ideal as it is not always easy to ensure correct even torque loading of the gasket. The applied torque has to overcome the friction between bolt and block and this friction is dependent on length of engaged thread as well as other factors. Using the original same length bolts immediately creates a creates a problem with the 2 bolts used in the dowel locating holes. These holes have significantly less thread due to the location of the dowels therefore these bolts will inevitably apply a different load to the head. The stud kit gets over this and ensures even loading of all 14 studs. See part number RG 075 if you are interested in purchasing these studs.