The mass-produced standard head studs/nuts suffer from compromised specification - both in material and machining quality. Worst affected are the threaded portions, giving rise to inaccurate torque-down; thread deformation, stud distortion and stretch, off-square seating of the nut to head and so on. Specific and tightly controlled design, machining, materials and manufacturing processes have been stipulated by Mini Spares to ensure a truly high standard finished product. This optimises even and accurate torque-down, eliminates stud distortion and minimises thread deformation. A bonus is prolonged usage. The use of special washers greatly improves even clampdown; the extra thickness used helps avoid thread bottoming when using seriously skimmed heads. A far superior clampdown is attained from the strength and accuracy of design and manufacture.

Consequently excessively high torque settings are not required. Although possible to torque these studs to 70lb ft, this will cause the threads to pull out of the block or severe distortion and deformation of current head gaskets to render this practice pointless. Where Genuine Rover or Payen head gaskets are used a torque setting of no more than 45lb ft is highly recommended to avoid distortion of the fire-ring. The non-stretch feature of these studs combined with this lower torque setting has proven totally reliable in all properly built engines. Fitting notes: - wash the studs and nuts thoroughly to ensure no swarf or dirt is in the threads - Fit studs into block dry, finger tight only - Oil thread very lightly before fitting nuts - Smear oil on base of nuts - Fit washers with large countersink to head, and on short studs only. The two smaller washers go on the studs either end of the rocker cover - Replace nuts after 4 or 5 uses to retain accurate torque-down (part no. 51K1193). Note: Where using to replace the head studs/nuts/bolt in an original Cooper 'S' block or block fitted with the 'S' type set-up (i.e. using a bolt at the water pump end), it is necessary to drill/tap the existing bolt hole/thread (5/16"UNC) out to 3/8"UNC to take the extra stud. If the original thread is made by using a Heli-coil type insert it is not easily corrected to take the extra stud since the hole will requiring plugging before re-drilling an tapping to the correct size.