What is the main benefit of the dual plug design?

The dual plug design allows for a more complete and consistent burn of the fuel-air mixture. This can lead to improved combustion efficiency, better power delivery, and a more responsive throttle.

What does the 'O-ring style' refer to?

The O-ring style seal means the cylinder head uses an O-ring gasket to create a seal between the head and the cylinder. This is a common and effective method for ensuring a tight seal in performance engine applications.

Specifications

Brand: S&S Cycle
Part #: 90-1491
UPC: 90-1491

S&S Cycle 66-78 BT Super Stock 3-5/8in Bore O-Ring Style Dual Plug Cylinder Head Kit - Natural

Name: S&S Cycle 66-78 BT Super Stock 3-5/8in Bore O-Ring Style Dual Plug Cylinder Head Kit - Natural
Brand: S&S Cycle
SKU: s-s-cycle-s-s-cycle-66-78-bt-super-stock-3-5-8in-bore-o-ring-style-dual-plug-cyl-t14-664024
Price: 1915.90 USD
Availability: BackOrder

$1915.90

On Backorder

Order now to reserve yours — we'll ship as soon as stock arrives. Full refund if we're unable to fulfill.

Key Features

Fits 1966-1978 Big Twin motorcycles.
Features a 3-5/8 inch bore size.
O-ring style seal for a secure fit.
Designed for dual spark plugs to improve combustion.
Natural aluminum finish for a classic look.
Built by S&S Cycle, a popular name in performance motorcycle engines.

This cylinder head kit is designed for 1966-1978 Big Twin motorcycles. Please verify compatibility with your specific motorcycle model and engine configuration.

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About this part

Product Details

If you're rebuilding the top end of your 1966-1978 Big Twin motorcycle, a solid set of cylinder heads is crucial for getting the performance you're after. This Super Stock cylinder head kit from S&S Cycle is built for those looking to get the most out of their engine. It features a 3-5/8 inch bore and an O-ring style seal, designed to work with dual spark plugs for improved combustion efficiency.

Crafted from aluminum, these heads offer a natural finish that looks clean and classic on your build. The dual plug design means you can get a more complete and consistent burn from your fuel-air mixture, which can lead to better power delivery and throttle response. S&S Cycle is well-known for making robust engine components, and this kit is no exception, offering a well-built foundation for your engine's performance upgrades. The 3-5/8 inch bore size is specific for certain Big Twin applications, so make sure it matches your engine's requirements.

Keep in mind that this kit is not CARB approved and cannot be shipped to California. For the best results, ensure you have all the necessary supporting components and refer to the manufacturer's installation instructions for proper fitment and setup.