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Engine Kits

Big bore engine kits for a Harley-Davidson engine involves replacing the stock cylinders and pistons with larger ones, effectively increasing the engine's overall displacement. This modification aims to improve the overall performance of the motorcycle. The larger cylinders allow for more air and fuel to be combusted, resulting in increased power and torque. Riders often choose this upgrade to enhance acceleration, throttle response, and overall riding experience. It's a customization option for those seeking a more powerful and performance-oriented Harley-Davidson motorcycle.

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$595.95 - $595.95
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$595.95 - $595.95
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MHP +6.4cc Pistons for S&S 4.250" Bore Cylinders 128/131 cubic inch setups MHP-P4250

In stock

Moonshine Horsepower +6.4cc Pistons are designed to be a direct replacement for 4.250" S&S 128 and 131 setups when running a high horsepower ca...

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$595.95 - $595.95
$595.95
$595.95 - $595.95
$595.95
$1,950.74 - $1,950.74
$1,950.74
$1,950.74 - $1,950.74
$1,950.74

MHP 131 Stage IV Upgrade Kit - Black

In stock

Moonshine Horsepower 131 Stage IV Upgrade Kit Transform your Harley-Davidson M8 Stage IV 131 SE into a powerhouse with the Moonshine Horsepower 131...

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$1,950.74 - $1,950.74
$1,950.74
$1,950.74 - $1,950.74
$1,950.74
$2,299.00 - $2,299.00
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$2,299.00

Moonshine Power Kit 128 Black w/highlights, oil cooled M8

In stock

Moonshine Power Kit by S&S Cycles - Cylinders black w/highlights - Oil Cooled Pump & Plate - 0904-0079 We have worked directly with S&S...

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$2,299.00 - $2,299.00
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$2,299.99 - $2,299.99
$2,299.99
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$2,299.99

Moonshine Power Kit 128, black w/o highlights, oil cooled M8

In stock

Moonshine HP Power Kit by S&S Cycles - Cylinders black w/highlights - Oil Cooled Pump & Plate - 0904-0081 We have worked directly with S&am...

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$2,299.99 - $2,299.99
$2,299.99
$2,299.99 - $2,299.99
$2,299.99
$3,599.95 - $3,599.95
$3,599.95
$3,599.95 - $3,599.95
$3,599.95

MHP S&S 132" M8 Power Pack - Stage II - Oil Cooled

In stock

Moonshine Horsepower S&S Cycles 132" Stage II Power Pack - MHP-492X Camshaft Kit Included Unleash the true potential of your Harley-Davidson ...

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$3,599.95 - $3,599.95
$3,599.95
$3,599.95 - $3,599.95
$3,599.95
$2,795.95 - $2,795.95
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$2,795.95

MHP S&S 132" M8 Power Pack - Stage I - Oil Cooled

In stock

Moonshine Horsepower S&S Cycles 132" Stage I M8 Big Bore Power Pack - No Camshaft Included Elevate your ride with the Moonshine Horsepower S...

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$2,795.95 - $2,795.95
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$2,795.95
$1,910.74 - $1,910.74
$1,910.74
$1,910.74 - $1,910.74
$1,910.74

MHP 131 Stege IV Upgrade Kit - Chrome

In stock

Moonshine Horsepower 131 Stage IV Upgrade Kit Transform your Harley-Davidson M8 Stage IV 131 SE into a powerhouse with the Moonshine Horsepower 131...

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$1,910.74 - $1,910.74
$1,910.74
$1,910.74 - $1,910.74
$1,910.74
$2,399.95 - $2,399.95
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$2,399.95

MHP 135 Piston and Cylinder Kit, Black Highlighted Cylinders

Low stock

Product Description: Moonshine Horsepower 135 Cubic Inch Piston and Cylinder Kit Elevate your Harley-Davidson engine's performance with our Moonshi...

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$2,399.95 - $2,399.95
$2,399.95
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$559.95 - $559.95
$559.95
$559.95 - $559.95
$559.95

ARP M-Eight Cylinder Studs & Head Bolt Kit, Feuling

In stock

Milwaukee Eight CYLINDER STUD AND HEAD BOLT KIT7/16 X 6.250 STUDS W/DOWEL RING - CHROME MOLY, QTY. 8STAINLESS 12 POINT HEAD BOLTS UHL 3.215, QTY...

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$559.95 - $559.95
$559.95
$559.95 - $559.95
$559.95
$3,389.75 - $3,389.75
$3,389.75
$3,389.75 - $3,389.75
$3,389.75

MHP 4.250" bore High HP Complete Upgrade Kit - Oil Cooled Heads - MHP-5050

In stock

Moonshine Horsepower +6.4cc Pistons are designed to be a direct replacement for 4.250" S&S 128 and 131 setups when running a high horsepower ca...

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$3,389.75 - $3,389.75
$3,389.75
$3,389.75 - $3,389.75
$3,389.75