Heavy Duty Valve Springs
Standard valve springs suffer from varying seat pressures from new and once subjected to cyclic operation (even for a short time) can lose tension rapidly. This loss of tension can lead to “valve float”, a condition whereby the valve is not returned cleanly to the valve seat, allowing it to bounce off the seat and releasing vital cylinder pressure. The resultant loss of pressure creates a misfire, followed by either erratic idling and/or stalling.
All valve springs lose tension after being installed – and because the original Ford valve springs are quite weak, even a small loss of tension can bring about this condition. Turbo boost pressure also works against valve spring tension on the inlet valves – the DOHC Ford 6 cyl inlet valve has an area of 3.5 sq inches approx, so for every pound of boost, roughly 3.5 lbs of valve spring tension is deducted from the spring pressure. For example, if the spring has 50lbs of seat pressure and the engine has 7 pounds of boost, the net effect is that valve spring tension is reduced by 24.5 lbs to only 25.5 lbs of seat pressure, which is inadequate for almost all applications.
Atomic H/D or Race springs are definitely not repackaged Ford V8 or Typhoon/Tornado springs (which fatigue just as quickly as the originals) but are custom wound from premium quality USA made nickel chrome vanadium spring steel, heat treated, shot peened, scragged and packed in matching sets of either 12 or 24 for use in all 4.0L SOHC and DOHC 6 cyl engines. Suitable for use with either standard or Atomic camshafts, no expensive cylinder head machining is required and the standard valve spring retainers, seals and locks are retained.