S&S Cycle Power Pack - 4.375" Stroke - Oil Cooled - Black w/Highlights - M8

$3,497.95


Delivery and Shipping

Ships Within 2-5 business days

For Pickup Call for availability

Features

  • Bolt-on kit
  • With updated fins
  • No case machining required
  • Forged pistons
  • Made in the USA
  • Includes oil pump/cam plate, pushrods, tappets, tappet cuffs, 550 camshaft, valve springs
  • Oil Pump/Cam Plate:
  • Precision machined from billet aluminum
  • Passage plugs removable for servicing
  • Independent scavenge sections for flywheel cavity and camchest
  • Debris screens in both scavenge pickups
  • Magnet in camchest to help to stop debris from entering oil pump
  • 44% flow increase on supply side and 58% flow increase on scavenge side
  • Pressure relief valve is adjustable with unit installed in engine
  • Pushrods:
  • Quickee pushrods
  • Tappets:
  • Hand assembled to exacting tolerances
  • Reduced valve train noise from start up to shut down
  • Close tolerances for low leak down rates
  • Tappet Cuffs:
  • Hard anodized black coating
  • Billet aluminum construction
  • Tappet stability in high lift and high rpm sitiuations

Specs

Product Name Performance Kit
Type Big Bore
Model Power Package
Color/Finish Black / Highlighted Fins
Features Includes Outer Drive Gears / Quickee Pushrods w/Gloss Black Covers
Stroke Length 4.375"
Displacement 124"
Bore Size 4.250"
Compression Ratio 11.1:1
Cam Drive Type Gear
Cooling System Oil Cooled
Units Kit
Riding Style Street

 

FITMENTS:

2025 Harley-Davidson Softail Fat Boy FLFB - -
2025 Harley-Davidson Freewheeler FLRT - -
2025 Harley-Davidson Softail Low Rider ST FXLRST - -
2025 Harley-Davidson Softail Low Rider S FXLRS - -
2025 Harley-Davidson Street Glide EFI FLHX - -
2025 Harley-Davidson Softail Heritage Classic FLHC - -
2025 Harley-Davidson Road Glide Custom FLTRX - -
2025 Harley-Davidson Road Glide 3 FLTRT - -
2025 Harley-Davidson Softail Breakout FXBR - -
2024-2025 Harley-Davidson Road Glide Police FLTRXP - -
2024 Harley-Davidson FLI Hydra-Glide Revival - -
2023-2025 Harley-Davidson FLTRT Road Glide 3 - -
2023-2025 Harley-Davidson FXBR Breakout 117 - -
2023 Harley-Davidson FLHFB Electra Glide Highway King - -
2022-2025 Harley-Davidson FXLRS Low Rider S 117 - -
2022-2025 Harley-Davidson FXLRST Low Rider ST 117 - -
2022-2023 Harley-Davidson FLHXST Street Glide ST - -
2022-2023 Harley-Davidson FLTRXST Road Glide ST - -
2022, 2025 Harley-Davidson Softail Street Bob FXBB - -
2022 Harley-Davidson FXRST Low Rider El Diablo 117 - -
2021-2024 Harley-Davidson FXBBS Street Bob 114 - -
2021 Harley-Davidson FLH Electra Glide Revival - -
2020-2024 Harley-Davidson FXST Softail Standard 107 - -
2020-2021 Harley-Davidson FXLRS Low Rider S 114 - -
2019-2022 Harley-Davidson FLHT Electra Glide Standard - -
2019-2020 Harley-Davidson FXDRS FXDR 114 - -
2018-2024 Harley-Davidson FLFBS Fat Boy 114 - -
2018-2024 Harley-Davidson FLHCS Heritage Classic 114 - -
2018-2023 Harley-Davidson FXFBS Fat Bob 114 - -
2018-2021 Harley-Davidson FLHC Heritage Classic 107 - -
2018-2021 Harley-Davidson FLSB Sport Glide 107 - -
2018-2021 Harley-Davidson FLSL Softail Slim 107 - -
2018-2020 Harley-Davidson FLDE Deluxe 107 - -
2018-2020 Harley-Davidson FXBRS Breakout 114 - -
2018-2020 Harley-Davidson FXBB Street Bob 107 - -
2018-2020 Harley-Davidson FXLR Low Rider 107 - -
2018-2019 Harley-Davidson FLFB Fat Boy 107 - -
2018-2019 Harley-Davidson FXFB Fat Bob 107 - -
2018-2019 Harley-Davidson FXBR Breakout 107 - -
2017-2025 Harley-Davidson FLHRXS Road King Special - -
2017-2025 Harley-Davidson FLHX Street Glide - -
2017-2025 Harley-Davidson FLRT Freewheeler - -
2017-2025 Harley-Davidson FLTRX Road Glide - -
2017-2025 Harley-Davidson Electra Glide Police FLHTPI - -
2017-2025 Harley-Davidson Road King Police FLHP - -
2017-2023 Harley-Davidson FLHXS Street Glide Special - -
2017-2023 Harley-Davidson FLTRXS Road Glide Special - -
2017-2022 Harley-Davidson FLHR Road King - -
2017-2022 Harley-Davidson FLHXSE CVO Street Glide

Payment & Security

Payment methods

  • American Express
  • Apple Pay
  • Bancontact
  • Diners Club
  • Discover
  • Google Pay
  • iDEAL Wero
  • Mastercard
  • PayPal
  • Shop Pay
  • Visa

Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.

S&S CYCLE

S&S Cycle Power Pack - 4.375" Stroke - Oil Cooled - Black w/Highlights - M8

$3,497.95

Features

Specs

Product Name Performance Kit
Type Big Bore
Model Power Package
Color/Finish Black / Highlighted Fins
Features Includes Outer Drive Gears / Quickee Pushrods w/Gloss Black Covers
Stroke Length 4.375"
Displacement 124"
Bore Size 4.250"
Compression Ratio 11.1:1
Cam Drive Type Gear
Cooling System Oil Cooled
Units Kit
Riding Style Street

 

FITMENTS:

2025 Harley-Davidson Softail Fat Boy FLFB - -
2025 Harley-Davidson Freewheeler FLRT - -
2025 Harley-Davidson Softail Low Rider ST FXLRST - -
2025 Harley-Davidson Softail Low Rider S FXLRS - -
2025 Harley-Davidson Street Glide EFI FLHX - -
2025 Harley-Davidson Softail Heritage Classic FLHC - -
2025 Harley-Davidson Road Glide Custom FLTRX - -
2025 Harley-Davidson Road Glide 3 FLTRT - -
2025 Harley-Davidson Softail Breakout FXBR - -
2024-2025 Harley-Davidson Road Glide Police FLTRXP - -
2024 Harley-Davidson FLI Hydra-Glide Revival - -
2023-2025 Harley-Davidson FLTRT Road Glide 3 - -
2023-2025 Harley-Davidson FXBR Breakout 117 - -
2023 Harley-Davidson FLHFB Electra Glide Highway King - -
2022-2025 Harley-Davidson FXLRS Low Rider S 117 - -
2022-2025 Harley-Davidson FXLRST Low Rider ST 117 - -
2022-2023 Harley-Davidson FLHXST Street Glide ST - -
2022-2023 Harley-Davidson FLTRXST Road Glide ST - -
2022, 2025 Harley-Davidson Softail Street Bob FXBB - -
2022 Harley-Davidson FXRST Low Rider El Diablo 117 - -
2021-2024 Harley-Davidson FXBBS Street Bob 114 - -
2021 Harley-Davidson FLH Electra Glide Revival - -
2020-2024 Harley-Davidson FXST Softail Standard 107 - -
2020-2021 Harley-Davidson FXLRS Low Rider S 114 - -
2019-2022 Harley-Davidson FLHT Electra Glide Standard - -
2019-2020 Harley-Davidson FXDRS FXDR 114 - -
2018-2024 Harley-Davidson FLFBS Fat Boy 114 - -
2018-2024 Harley-Davidson FLHCS Heritage Classic 114 - -
2018-2023 Harley-Davidson FXFBS Fat Bob 114 - -
2018-2021 Harley-Davidson FLHC Heritage Classic 107 - -
2018-2021 Harley-Davidson FLSB Sport Glide 107 - -
2018-2021 Harley-Davidson FLSL Softail Slim 107 - -
2018-2020 Harley-Davidson FLDE Deluxe 107 - -
2018-2020 Harley-Davidson FXBRS Breakout 114 - -
2018-2020 Harley-Davidson FXBB Street Bob 107 - -
2018-2020 Harley-Davidson FXLR Low Rider 107 - -
2018-2019 Harley-Davidson FLFB Fat Boy 107 - -
2018-2019 Harley-Davidson FXFB Fat Bob 107 - -
2018-2019 Harley-Davidson FXBR Breakout 107 - -
2017-2025 Harley-Davidson FLHRXS Road King Special - -
2017-2025 Harley-Davidson FLHX Street Glide - -
2017-2025 Harley-Davidson FLRT Freewheeler - -
2017-2025 Harley-Davidson FLTRX Road Glide - -
2017-2025 Harley-Davidson Electra Glide Police FLHTPI - -
2017-2025 Harley-Davidson Road King Police FLHP - -
2017-2023 Harley-Davidson FLHXS Street Glide Special - -
2017-2023 Harley-Davidson FLTRXS Road Glide Special - -
2017-2022 Harley-Davidson FLHR Road King - -
2017-2022 Harley-Davidson FLHXSE CVO Street Glide
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