HPR Aluminum 402 LS Long Block

  • Sale
  • Regular price $10,995.95

HorsePower Research

HPR 402 LS Long Block 

HPR's popular 402.  Starting with a fresh GM LS2 aluminum cylinder block as the foundation we fill the block with forged crankshaft, rods, and pistons all machined and assembled here in house.  The 4" stroke crank will greatly aid in torque production over a standard LS 3.62" stroke unit while allowing better utilization of higher flowing cylinder heads from PRC and our own custom ground camshaft. 

Every component is thoroughly measured, cleaned, and assembled for proper fit under the most extreme uses. 

 Long block is completely assembled, balanced and blue printed to exacting specifications set by Erik.  We include (unless otherwise stated), all covers installed with full measured valvetrain ready for your intake, oil pan, and accessories to make the install as easy as possible. 

Looking for a custom build? We can do that too!  Ask your sales rep for details for more info today sales@horsepower-research.com



  • New GM LS2 aluminum block
  • ARP Main stud kit
  • Forged steel crankshaft by K1 Technologies
  • Forged connecting
  • HPR spec pistons by Wiseco
  • HPR designed and spec piston ring pack by Wiseco
  • All components Ultra Sonic washed before assembly
  • Machine work and assembly done in house at HPR
  • Your choice of 24x or 58x crankshaft reluctor wheels
  • Short or Long post crankshaft for normal oil pump or OE dry sump
  • PRC CNC ported cylinder heads
  • HPR custom ground cam to your specifications
  • GM LS7 lifters and trays
  • HPR custom chrome moly pushrods
  • MLS head gaskets
  • ARP head bolts
  • Melling 355 Hi press/Hi volume pump
  • C5R timing chain set
  • GM engine covers. (front, rear, valley)
  • All engine block and head plugs


 Items required to finish:

  • Engine sensors (except for cam position, included with front cover)
  • Valve covers
  • Intake manifold
  • Harmonic balancer
  • Oil pan and pickup tube
  • Water pump
  • Accessories
  • Spark plugs


***ALL ENGINES ARE BUILT TO ORDER - Please contact your sales rep for build time and ETA