346ci Long Block 5.3 Gen IV Aluminum Crate Engine

The Thompson Motorsports 346ci Long Block is a performance-oriented engine assembly built for power and reliability. It starts with a 5.3 Gen IV aluminum block, bored to 3.898" and paired with a 3.622" GM nodular reman crankshaft and 5.7L flat-top pistons, resulting in a 346 cubic inch displacement. The engine achieves an approximate 11:1 compression ratio. Key performance components include Frankenstein ported 862 cylinder heads with cathedral ports, a Cam Motion 210/214/114 camshaft, and a Melling High-Pressure oil pump for consistent lubrication. It also features GM Reman 6.098" connecting rods with .945" pins, TMS LS7 style lifters, and a trunion-upgraded TMS rocker arm kit. The assembly is completed with GM front, rear, and valley covers, an oil pan, a stock replacement balancer, water pump, and NGK spark plugs. This long block is designed for easy integration, typically requiring approximately 5+ days for preparation before pickup. It utilizes a 58X reluctor for compatibility with modern GM engine management systems.