425hp Corvette Engine (4-bolt Main, Snowflake Intake, All Forged, Traco Nos Cam)

  

I recommend this solid lifter balanced and blueprinted combination just finished up at my shop recently.. It has new genuine GM stellite cap solid lifters, special Traco NOS camshaft --special grind upgrade to 435hp. New moly rings, new King bearings, digitally balanced. Special high performance Rect port heads. GM standard bore forged dome pistons.

New hardended retainers and locks. I could go on and on.

4 weeks or 160 hrs labor spent on the build + around 8,000 in parts! I will send the blueprint sheets below. WOW-425HP 396 refurbished engine with GM part number dome forged L78 pistons. #3855962 FACTORY 4-BOLT MAIN block, VERY RARE #3673858 Rect port special HIPO heads. Look up the block part number and head part numbers.

Block is stamped with IF suffix code that comes back in Corvette book code for 1966 Corvette 425hp. NOTE: Valve covers can be painted orange no charge if you want that to be technically more correct for 1965 Corvette L78 425hp application. Approximately 4 weeks full time work to restore and refubish this engine back to look like it would have when it came off GM's assembly line in 1960's.

Willing to sell for less to move the engine... VERY SPECIAL NOS Traco solid lifter camshaft installed. Look of Traco--very special deal.. Major over-hauling and refurbished with torque plate honing of cylinders in standard bore! Using hand selected factory 4-bolt main hi-po engine blocks. New true roller double row timing sets.

New cam and lifters with ONLY Genuine GM hardened face lifters used! New melling oil pump with steel pinned drive shaft. These are awesome high performance engine combinations perfect for your Corvette, Camaro, or other high performance Chevrolet muscle car! Blueprint sheet for this engine below.

581 lift made by Engle cam for Traco. Installed brand new out of the box NOS! 1965 396 L78 Corvette Blueprint Sheet (Rebuilt Balanced & BluePrinted in 2025). Genuine GM #6223 forged crankshaft.

SA Gear True roller double row timing set. Hastings Plasma Moly Ring Set. Forged Pistons GM #3881456 DOME L78 425HP 11.0:1. Special Order NOS TRACO Road Race Camshaft Made Custom for TRACO SCCA race team.

587exh lift with 1.72 ratio. 341 Exh lobe (Before Rocker Ratio). Genuine GM Solid Flat Tappet Lifters (With Fused on Stellite Hardened Wafer Face). Piston to Valve Clearance >. Crankshaft forged #6223 3.766 stroke GM.

030Digitally Balanced in 2025 On Winona Van Norman Balance Machine. Engine Block GM Casting Number 3855962 (Special High Performance 4-BOLT MAIN).

Engine Block Standard Bore Torque Plate Honed in 2025 w/ 3. Sunnen Stone JHU818 for Moly Ring RA Finish.

Heads GM Rectangular Port (1965 Casting Date) Used originally on 425-450hp Corvette C2. 2.190/1.880 21-4N Stainless valves with Bronze valve Guides (Manley/Engine Pro valves). Undercut Stems, Hardened Tip, One Piece Forging, Hard Chrome Plated Stems.

Premium True Dual Valve Spring Duplicate of GM#14097002 w/ 1.270 Coil Bind. Metal Clad High Temp Positive Valve Seals.

Hardened Locks and Heat Treated 4140 Chrome Moly Steel Retainers (10 degree Super Lock). 1.900 Installed Height, 115 psi Seat pressure 335psi at full lift 1.310-1.330. Long Slot ZL1/L88 style Rocker Arms 1.72 Ratio, Machined Extra oil Gulls. Engine Pro HP 7/16 Rocker Studs 8740 Chrome Moly Rated to 190,000 psi tensile strength. Melling M77 oil pump with steel pinned driveshaft.