The LQ9 came with flat top pistons. (This raised the compression ratio, horsepower, and torque.) The LQ9 had injectors with a slightly higher flow rating. If you don’t have the VIN code, you will need to inspect the pistons. This means removing the cylinder heads or using a Borescope. Special Notes. The 1999-2000 LQ4 had cast iron cylinder heads.

A popular upgrade to the LQ4 and LQ9 is to install a set of LS3 heads and intake. The LS3 heads will fit on any LS block with a minimum 4.000 in. bore. However, the LS3 had a 4.065 in. bore. This means that the valves will be closer to the cylinder walls. Less space around the valve can limit the air flow.

Related Products: Camshafts & Valvetrain, Cylinder Heads, Engine Assemblies, Oiling Systems, Other Engines & Components, Pistons & Piston Rings

Engine Block Specifications. Casting Numbers: 12551364, 12573581, 12577184. Material: Iron. Displacement: 6.0L / 364 cid ...

The LY6 was introduced in 2007. It replaced the LQ4 and LQ9 as the Vortec 6000. Along with the LY2, LY5, and LMG, it was one of the first 4th generation, LS truck engines. The LY6 used Variable Valve Timing (VVT). This helped it make more Torque and Horsepower than the previous 6.0L engines. It was available in GM pickups until 2010.

Displacement Markings and Block Material. The displacement will be cast into the metal at the front (or rear) of the block, just below the cylinder head. While you're there, check to see if the block is aluminum or cast iron. If you're not sure, check it with a magnet. Cast iron is magnetic while aluminum is not. Timing Cover

Chevrolet's 3rd and 4th generation small block engines are generally known by their RPO code. You can determine the RPO code if you have the Vehicle Identification Number (VIN) from the original vehicle. Locate the 8th digit of the VIN. Consult the tables below to …

We have torque specs for many popular engines. Just click one of the links below for more information. ...

Gen. 3, Iron Block, LS Engines. The following specs apply to RPO codes: LR4 LM7 L59 LQ4 LQ9 **Click the blue links in the table for more detailed information** Fastener Type First Pass Second Pass Final Pass Main Caps Inner Bolts 15 ft.-l... Chevrolet …

Gen. 3, Iron Block, LS Engines. The following specs apply to RPO codes: LR4 LM7 L59 LQ4 LQ9 **Click the blue links in the table for more detailed information** Fastener Type First Pass Second Pass Final Pass Main Caps Inner Bolts 15 ft.-l... Chevrolet …