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R&D High Performance Dual Valve Spring Kit

Dual Valve Spring Kit

Our Price: $449.95

Product Code: 612-93001

R&D has developed an economical solution for upgrading the valve train by offering a series of upgrade parts that will work great with the O.E.M. retainer and valve seals. R&D has documented that the seat tension or pressure on the stock springs is a low 52-55 pounds, and coil bind on the stock springs occurs .050” after full lift on the stock cams. As an industry rule or standard, as boost levels are increased to the engine, the valve spring seat pressure should be increased 1-2 pounds per pound of boost. As an industry rule, as RPM'S are increased, the spring pressure at full lift should be increased as well to reduce or eliminate valve float at high rpm frequencies. With the stock springs “short lift travel” shimming is NOT an option. Valve Springs MUST be upgraded.
Also to consider is valve spring travel at full cam lift, and to have enough spring clearance freedom to run high performance camshafts or add additional spring tension pressures without coil bind issues. The R&D spring kit parts were developed and used with stock retainers during the 2009 season and have proven their performance with an APBA/IJSBA Pro Open National Championship.
R&D dual springs are a “lightweight design” and manufactured from ultra clean, high tensile material with multi step surface treatments to improve fatigue strength and reliability. NOTE: R&D Spring Kits must use the R&D Bottom Spring Retainer Cups kit Pt. # 612-93006 for proper assembly and seat pressures!
  • Engine Tuning Features
  • • 70-75 pounds at seat, 140-150 pounds at full lift (standard spec.)
  • • Shim friendly, add R&D spring collar base shims to add 2 pounds per .010 shim added
  • • Allows the use of higher lift cams (up to +.080)
  • • Linear spring pressure curve allows smooth precision valve control, adds to overall horsepower
  • • High performance materials and surface finishes add to reliability

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