Chevrolet Performance Parts
Click on image to zoom

17802825 - COPO LS 427 425hp Crate Engine

This product may require vehicle validation(s) for proper fitment. Please contact us to confirm correct vehicle fitment and usage.

(0) Reviews: Write first review
17802825
FREE 48 State Shipping!
Sold
Availability: Discontinued
Shipping: No Longer Available

Description

The COPO 427 for A Stock competition uses the large-bore cylinder block and high-flow cylinder heads of the LS7 engine and complements them with a high-compression rotating assembly to deliver big power from its large displacement. Its lightweight aluminum block and heads revive the spirit of the original ZL-1 all-aluminum 427 big-block that helped forge the COPO legacy in 1969.

Specs:

  • Displacement: 427 cu in (7.0L)
  • Compression Ratio: 13.5:1
  • Cylinder Block: LS7 cast aluminum
  • Bore x Stroke (in): 4.125 x 4.100
  • Crankshaft: Forged steel
  • Connecting Rods: Forged steel
  • Pistons: Forged dome
  • Cylinder Heads: LS7 aluminum
  • Induction: Natural
  • Intake Manifold: Holley
  • Camshaft Type: Hydraulic roller
  • Camshaft Lift (int./exh.): .595/595-inch

    • ENGINE:

  • Chevrolet Performance LS7 aluminum block
  • 4.125" bore x 4.00" stroke
  • Static compression ratio - 13:1 nominal
  • Callies 5140 crankshaft
  • Callies 4340 H-beam rods
  • 6.100" C-C length
  • .928" pin bore diameter
  • Clevite H-Series heat-treated tri-metal rod and main bearings
  • Mahle 2618 alloy forged domed pistons
  • Graphal coating
  • Hard-anodized top ring groove
  • Friction-coated skirts
    Mahle .043" x .043" x 3mm piston rings
  • Ductile iron top with radius molybdenum face
  • Plain cast iron tapered 2nd
  • Chrome-plated oil rails with low-tension expander
    Chevrolet Performance steel billet hydraulic roller camshaft
  • Duration -- 233?/276? @ .050" lift
  • Theoretical valve lift -- .630"/.630"
  • Lobe centers -- 107?

    VALVETRAIN:
    Chevrolet Performance "Ceramic Ball" high-rpm hydraulic roller tappets
    3/8" diameter LS7 pushrods
    1.8:1 ratio LS7 rocker arms with roller trunions
    PSI "Max Life" beehive valve springs
    Hardened steel spring seats
    Lightweight steel retainers
    Fully CNC'ed aluminum cylinder heads -- based on LS7
    275 cc nominal intake port volume
    89 cc nominal exhaust port volume
    70 cc nominal combustion chamber volume
    Del West titanium intake valves -- 2.205" head diameter x 7mm stem
    Lightweight sodium-filled exhaust valves -- 1.615" head diameter x 7mm stem
    Fel-Pro Performance multi-layer steel head gaskets with raised cylinder sealing bead
    Internal wet sump oil pump
    Deep-sump cast aluminum oil pan --
    6-quart capacity
    SFI-approved damper
    Billet electric water pump
    Chevrolet Performance/Holley "Hi Ram" intake manifold
    Whipple billet throttle body -- 102mm blade

    FUEL SYSTEM:

  • 42 lb/hr @ 58 psi with EV6/USCAR connector

    ENGINE CONTROLS & IGNITION:
    Cable-actuated throttle
    Production LS7 ignition coils
    Production LS7 secondary wires
    GM sensors

    • Application List

    Universal

    Details

    Categories

    Shipping Information

    • Item Requires Shipping
    • 500.0 lbs.
    • W34.3000” x H31.0000” x L43.5000”
    • Free Shipping!
    • This item will require a special quote for shipping charges.
    • No Longer Available

    Customer Reviews

    Comment Total Reviews (0)

    Write the First Review!

    You must login to post a review.

    Trusted Specialists GM engine & parts specialists
    Located in the USA Owned, operated, & employed
    Need Assistance? Call us at 888-748-4655
    Mon-Thu 8am-6pm EST
    Fri 8am-5:30pm EST
    Have a Question Email us and we'll get back to you within 24 hours