FEATURES: - You do not need the return side chain tensioner or chain guide when using this equipment. - The head space can be adjusted between 0-4mm so the cam spacer is unnecessary. (L4 is 0-3mm) - Rocker guides are lighter and slimmer and help increase the performance of the motor. - Reduced friction from the timing chain friction and stabilized valve timing. - RPM Tolerance 13, 000 RPM - Machined Chromoly Sprocket - Duralumin Plate - Chromoly Slide Plate