Valve Spring Set for 5.9L 6.7L Cummins

The Hamilton Cams Valve Spring Set is engineered to enhance the performance and reliability of Dodge 5.9L and 6.7L Cummins engines from model years 1998.5 through 2018. Standard 24v springs typically provide 78-82 lbs of seat pressure, which is insufficient for controlling the valvetrain effectively when boost or drive pressure exceeds 35 psi. This can result in valves being blown open, leading to reversion. Reversion allows exhaust gases into the cylinder during the intake stroke, which negatively impacts power by increasing injection timing delay, reducing peak cylinder pressure and temperature, and prolonging the combustion cycle. These #103 springs are designed with a lowered nose pressure, recently adjusted from 220lb to 180lb, to promote longer cam life compared to springs with over 250lb nose pressures. They are recommended for applications up to 4,500 RPM. Exceeding this RPM range with the #103 springs may lead to broken or cracked retainers due to valve float and harsh valve actuation, at which point the #110 springs would be necessary. For warranty on Hamilton Cams, their springs and tappets must be used. Tool steel retainers are available separately. This product will not ship to California.