Chevy LS7 12° Heads 4.130 bore, 4.000 stroke, 6.125 rod, 1.120 CH, -4.6cc Flat Top 1.5mm, 1.5mm, 3mm rings (CP Bullets BLS1204-005)

You need the engine code, bore size, stroke, rod length, pin diameter and target compression ratio. These determine the correct piston compression height and crown design.

Ring gaps must be set by your engine builder based on fuel type, boost level and the intended rpm range. Forced-induction engines usually require larger gaps.

Yes. Forged pistons handle detonation and high cylinder pressure better than cast units. Your builder should set the piston-to-bore clearance to suit your application.

For the BLS1204-005 pistons, a typical bore clearance of 0.0030" to 0.0035" is recommended. However, this may vary based on the specific application and operating conditions, so always consult with your engine builder for precise measurements.

The BLS1204-005 pistons provide a compression ratio of approximately 11.1:1 when used with LS7 cylinder heads that have a 70cc combustion chamber. Ensure that your engine's overall setup, including head gasket thickness and any modifications, is taken into account for accurate compression calculations.

The BLS1204-005 pistons come with a ring set featuring 1.5mm x 1.5mm x 3.0mm thickness. It's crucial to set the correct ring gaps according to your engine's specifications and intended use.

The BLS1204-005 pistons weigh 484 grams each. While lighter pistons can improve engine response and reduce rotating mass, it's essential to balance them with the rest of the rotating assembly to maintain reliability and performance.

Yes, the BLS1204-005 pistons may require specific machining for proper fitment, including verifying bore size and ensuring correct ring land dimensions. Always consult with your engine builder to confirm any machining needs based on your engine's configuration.