Top End Components
Unlock the hidden potential of your engine with powerful Top End upgrades from Zipper’s Performance Products. Zipper’s Performance keeps specially CNC-machined factory heads in stock for super-quick turnaround (on an exchange basis) for Twin Cam® and Sportster® engines. Twin Cam® big bore cylinder conversions for 88 to 95” and 96 to 103” are also stocked, fitted with Wiseco forged pistons in three different compression ratios for fast turnaround exchanges. Zipper’s Performance also stocks pistons, valves, guides, valve spring kits, and other critical top end parts from the industry’s most renowned manufacturers like AV&V®, Axtell®, Baisley®, Crane®, Hastings®, JIMS®, Manley®, S&S®, and Wiseco®.
- Twin Cam® Performance Cylinder Heads
- Twin Cam® Performance and Replacement Valves
- Twin Cam® Valve Guides and Seals
- Twin Cam® Valve Spring Kits
- Twin Cam® Cylinder Head Accessories
- EV Big Twin Performance Cylinder Heads
- EV Big Twin Performance and Replacement Valves
- EV Big Twin Valve Guides and Seals
- EV Big Twin Valve Spring Kits
- EV Big Twin Cylinder Head Accessories
- EV Sportster® Performance Cylinder Heads
- EV Sportster® Performance and Replacement Valves
- EV Sportster® Valve Guides and Seals
- EV Sportster® Valve Spring Kits
- Shovelhead Performance Cylinder Heads
- Shovelhead / Iron XL® Valves
- Big Bore Cylinder Kits
- Piston Kits
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Add Torque and Power to any production Twin Cam® or Evolution® head with our...
SportMax heads include blueprinting work similar to the Stage I WorkHorse, with...
Put a set of our Stage III ThunderSport heads on your Sportster® to really...