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TThe LSx 427ci Boosted Complete Engine was built for customers that are looking to run 20-30 psi of boost and 1000hp +.

Compression Ratio: 9.5:1
Operating Range: 2500 – 6700rpm
Required Fuel: 91+ Octane Pump Gasoline 

Trust Golen Engine for the expertise and capabilities needed to get the most out of your new Chevy LSx 427 crate engine. Our experience with this racing engine means we can ensure it delivers the power and performance you need to rule the road. This LSx 427 supercharged crate engine is another of the many different customizations we offer for all kinds of turbo applications.

Our technicians have the know-how to customize your engine so you get exactly what you want out of it, and we offer a wide selection of configurations to suit you. With our in-house machine shop services, you’ll also know that everything we do will be done to the same exacting standards, giving you peace of mind.

No other provider of custom engines has as much to offer you as we do. When you come to us for a 427 LS engine or something else, you can depend on getting the best service. Read on to learn more about the specifications for the LSx 427 crate engine.



  • New GM LSx Cast Iron Block
  • Zero Decked
  • Bored 4.125”
  • Honed with Torque Plates and Pressure Washed
  • New Durabond Cam Bearings Installed
  • Line Honed
  • ARP Main Studs


  • Wiseco Forged Pistons, tool steel wrist pins


  • Clevite H-Series Main and Rod Bearings


  • Comp Cams Custom Hydraulic Roller


  • GM Oil Pan (Camaro, Corvette, GTO or Truck)
  • GM Timing Cover
  • GM Rear Cover
  • GM Lifter Valley Cover
  • GM Valve Covers


  • Powerbond SFI
  • ARP Damper Bolt


  • Callies Dragon Slayer 4340 Forged Steel
  • 4.000” stroke
  • Internally Balanced Front and Rear


  • Callies 4340 Ultra Forged H-Beam
  • 6.125” Length
  • ARP 2000 Rod Bolts


  • Stainless Steel Rings Gapped for Boost


  • Comp Cams Hydraulic Roller

Timing Sets:

  • Cloyes Billet Roller Hex Adjust Z-Chain

Oil Delivery:

  • Melling Performance
  • GM Pick Up Tube
  • GM Windage Tray


  • Cometic MLS Head Gaskets .051”
  • GM Cover Gaskets



  • Golen Aftermarket LS Aluminum CNC Ported
  • Three angle performance valve job

Intake Valves:

  • Stainless Steel 2.20”

Exhaust Valves:

  • Extreme Duty Inconel Stainless Steel 1.6”

Head Bolts: 

  • ARP Performance Heads Studs 6-bolt

Combustion Chamber:

  • 70cc


  • 380CFM @ .650” Lift


Spring Kit:

  • Polished Double Valve Spring
  • Titanium Retainers and Hardened Locks


Rocker Arms:

  • GM Factory 1.7 Ratio, Comp Cam Trunion Upgrade



  • Smith Brothers 3/8 .083” Wall Hardened


Ignition System:

  • Autolite Racing Spark Plugs


Dyno Test Service:

  • Run Engine for Full Break In and Power Test
  • 2 Oil Changes using Joe Gibbs Break In Oil
  • Graphs Listing HP, Torque and all Engine Vitals


We are able to build your LSx 427 engine to match just about any specs you desire, so if you do not see it just ask us! Each Golen Engine comes standard with a one year no mileage limit warranty to keep you confident and covered. When you purchase one of our LS HP or Hot Rod Series Street Engines you will receive a full spec sheet listing the exact components your engine was built with. We will also provide you with a complete Set Up Guide as well as full phone tech support to aid you with the installation process. It is mandatory for you to contact Golen Engine Tech Support before starting your engine for the first time and you can reach our Tech Support Line at 1-800-591-9171 ext 2. Each Golen Engine Performance Street Engine comes standard with a “One Year No Mileage Limit Warranty” to keep you confident and covered! Feel free to contact us anytime for help choosing the perfect performance engine combination!!