Offered is a documented 1969 Chevrolet Mark IV Big Block 427 engine featuring verified 4.00" stroke,
.030 overbore (~433 CID), and high-compression domed pistons consistent with L72 performance
builds. This is NOT an unknown core — displacement has been mechanically verified and internal
components inspected and photographed.
This came down from wife's grandfather who was an amateur race car machinist and mechanic for 70 years. Due to a passing away in family, we are being forced to sell it to handle some financial items. So, please respect the bid process and be fair.
Engine Identification
1 Casting Number: 3963512
2 Casting Date: May 27, 1969 (E27 9)
3 Block Type: Mark IV Big Block Chevrolet
4 Main Caps: 2-bolt main (correct for many performance builds)
5 Displacement: 427 CID verified via stroke measurement
6 Current Size: .030 over (~433 CID)
Internal Inspection Details
1 Verified ~4.00" crankshaft stroke
2 High-compression domed pistons
3 Clean cylinder walls with visible crosshatch
4 Performance rotating assembly
5 Deck surfaces professionally machined during rebuild
6 Mechanical fuel pump setup retained
7 Oiling system intact with pickup installed
Performance Lineage Assessment
Based on piston design, compression characteristics, and internal geometry, the engine aligns closely
with L72 427 performance specifications (originally rated 425 HP). The deck stamp was removed
during prior machining, which is common during professional rebuilds, but identification is supported by
casting date, internal configuration, and measured stroke.
“Appreciate the interest — this is a verified 427 short block with measurement documentation. I’m open to serious offers near asking. Let me know if you’re looking for a project at this level.”
The deck stamp was removed
during prior machining, which is common during professional rebuilds, but identification is supported by
casting date, internal configuration, and measured stroke.
Engine is currently a complete short block configuration. Stored indoors on an engine stand and rotates
freely. Inspection and refresh recommended prior to installation as with any vintage performance
engine
• Great candidate for rebuild or performance swap
• Comes as shown — detailed photos included
💰 Market Comparables:
• Similar rebuildable/Yours comparable listings often priced $4,000–$20,000 depending on completeness and matching status.
🚗 Why This Matters:
The 427 BB Chevy is iconic in muscle car history — sought by collectors and builders alike for Chevelle, Corvette, Camaro, Impala and more.
📦 Shipping / Pickup: Local pickup preferred, loading assistance available.
🎯 SERIOUS BUYERS ONLY — Priced to move quickly. Make your BEST OFFER — open to negotiate.
