Turn your “Sleepy” 96 Inch engine Into a “Sleeper” 103 incher! Cylinders (supplied on an exchange basis) are precision bored and honed on torque plates from 3-3/4” to 3-7/8” and fitted with forged flat-top pistons. A complete top end and cam change gasket set included, along with Red Shift cams designed to be used with stock heads. Two versions are available, with cam profiles selected that shine in three distinct power ranges.

517-320 includes Red Shift 525 cams and is the best choice for riders who want maximum early torque (2000-4500 RPM) for excellent pulling and passing power in heavy payload applications.

517-323 includes Red Shift 528 cams; best power is developed between 2500-5000 RPM, great for medium weight payloads with a sportier mid-range and upper end over the 525.

***Cylinder/piston kits available separately. #517-320 and #517-323 are designed to re-use the factory pushrods.

All kits can be purchased whole or in any combination of desired components, please contact our sales department at 410-579-2828 for more details and pricing.

***To ensure you enjoy a premium experience with a Zipper’s Engine Kit, Please fill out a Job Order Sheet prior to completing an order on the website.
Click here for Zipper’s Job Order Sheet


Not legal for sale or use in California on any pollution controlled motor vehicle.
Not legal for sale or use on any EPA pollution controlled motor vehicle.

Weight 1 lbs
Emissions Compliant

Engine Type


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