Ultralite Adjustable Shaft Roller Rocker Set, 1.7 Ratio YT6737Ultralite Adjustable Shaft Roller Rocker Set, 1. 7 RatioSuit AFR GM LS3 260cc Heads YT6737 6737 Yella Terra has developed shaft and pedestal systems for late model engines that have less than half the nose weight of other rocker designs to correct valve float when some performance camshafts are used with lightweight valve train components and conical springs. The result is greater RPM potential without sacrificing strength or reliability. Standard and