Dart 11011112 Pro 1 LS1 Aluminum SB Chevy Cylinder Heads Assembled (1 head)

The Dart LS1 style high performance cylinder head has better air flow, more efficient combustion, and more user friendly features than production LS1 castings - and costs less than comparable OEM heads. The Dart LS1 head retains stock valve angles, stock valve locations and stock accessory mounting holes to make installation easy. Virtually everything else has been improved.

Premium alloy: Dart aluminum heads are cast from virgin 355-T61 aerospace alloy for superior strength and integrity.
Extra thick walls provide material for porting.
Additional metal above the ports accommodates valve train upgrades.
Standard multi-angle intake, radiused exhaust seats and CNC machined valve bowls enhance flow.
Manganese bronze valve guides and interlocking hardened valve seats ensure long term reliability.
Racing inspired combustion chamber improves flame propagation and increases air flow.
Intake valve diameters are matched to port volumes, with 2.02 inch valves for 205cc ports and 2.05 inch valves for 225cc intake runners. - Optimized 85cc exhaust ports are 15cc larger than stock and 1.60 inch exhaust valves scavenge the cylinders quickly. - Bolt on compatibility: Standard valve angle and spacing are retained to allow use of off the shelf pistons and valve train components. - All cylinder heads sold individually.