Randall Aase of Aasco Motorsports has been providing Porsche owners performance valve springs since 1981. Randall Aase has built several championship winning race engines with the Porsche platform from IMSA to the 24 hours of Le Mans. They have also been used by the top contenders in IMSA, ALMS, GRAND AM, SCCA as well as PCA, POC even factoring in other manufacturer’s championship efforts. 911, 934, 935, 962, 993 have benefited from the cutting edge material and design detail in spring manufacturing to control Harmonic Frequencies associated with racing cams. Street performance users have benefited in the fatigue resistance imparted by the careful detail paid to not only the proprietary alloy but the heat treatment during and after the winding of the spring as well as X-ray inspection for quality control. They are designed and manufactured to specifically fit the envelope of a Porsche application not a spring from another use. It operates a higher natural frequency than the original spring for racing and at the very least minimizes damage from over rev in track day situations.