Product Information
Wrinkle black finish Keep your stock crankcases and max out the horsepower of your late Big Twins Gear drive 640 Easy Start Cams included in 07-up kits Chain drive 640 Easy Start Cams included in 99-06 kits Wrinkle black powder-coat finish heads match factory finish Requires crankcase boring to accept 4-1/8in. cylinders Minimal engine height change - .096in. and original serial numbers retained Kits include S&S Super Stock 91cc cylinder heads 10.8:1 CR Stroke 4-5/8, bore 4-1/8in., cylinder length 5.013in.
