Almost every diesel engine we come across, has a significantly undersprung valvetrain when it comes to absolute power production. The VAG 8 valve PD engine is no exception.

With the stock valve springs, the valve control under high boost and high rpm operation becomes affected. This is not ideal when we are wanting to make the valve events happen at a specific time, and for a specific duration.
Exhaust manifold pressure is one of the key things that makes valve control a problem on highly tuned diesel engines. Put simply, the exhaust valve will not close in time, and it is possible that under high rpm high boost situations (accompanied by high EMP), that the exhaust valve may come into contact with the piston. This will not always result in damage, but it is a situation that is best avoided.
With these valve springs, the ability to run at higher performance indexes is achieved, while maintaining the ability to control the valve events decisively and accurately.

The single spring kits are a mild performance upgrade, suitable for those using stock camshafts, but that are having valve float issues or severe drops in torque above 4400rpm.
Single spring kits come as a set of 8 springs. Springs made from high tensile heat treated steel, designed to survive the harshest of engine conditions.

The dual spring kits are a high performance upgrade. Suitable for those using performance camshafts, which require a greater level of valve control, due to the accelerations of the valve given the ramp rate of the cam. They also provide better valve control, after the valve has landed in the seat at a faster closing ramp speed, thus better valve sealing is achieved earlier in the cycle.
Dual spring kits come as a set of 16 springs (8 inner and 8 outer) 8 titanium valve spring retainers, and 16 valve locks. The springs are made from high grade high tensile heat treated steel, designed to work together in harmony for the ultimate in valvetrain modifications. Valve spring retainers are cnc machined for the best possible finish, fitment and strength, and are produced from ultra strong titanium ingot. Valve locks are through hardened for absolute maximum strength and rigidity.

All valve springs are made to exact specifications, and are direct replacements for the standard springs.

A running in procedure of 3 heat cycles at light load is required for these spring kits.

All spring kits come with 12 months warranty.