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12729604 Notes:
- Max HP: 525
- Max Stroke: 4.00"
- Street Use
- Production oiling system
- 6-bolt iron main bearing caps
- 9.240" deck height
- Use only LS1, LS6, LS2, L92/LS3-style cylinder heads
- Provisions for Active Fuel Management
- Great for stroker cranks for even more cubes
12729604 supersedes 12673475
Emissions Note:
This part is only legal for sale and use on Uncontrolled (Non-Emissions Controlled) Vehicles or on vehicles used solely for the purposes of closed competition racing.
CLICK THIS LINK FOR IMPORTANT CARB & EPA EMISSIONS INFORMATION ABOUT THIS PART
GM Gen III & Gen IV Small Block Performance
Chevrolet Performance LS Series Engine Blocks are driving a new generation of street and racing enthusiasts by providing a foundation for serious performance achievements. Chevrolet took a chance with the LS engine, staying true to the pushrod small-block and continued to develop this technology to the point that building a daily-driven, 500-plus HP car is no big deal. If you are building a full out track-only racing engine or a mild street cruiser there is a strong and durable LS cylinder block available to assure that you produce the power you require safely!
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Features:
- Deep-Skirt Casting (the block side extends below the crankshaft centerline)
- 6-Bolt Cross-bolted Main Caps
- Provisions for the latest in Engine Control Management
- 9.240" Standard Deck Height
- 2.560" Standard LS Crankshaft Journal Diameter
