Chevy LS2 4.000" 403ci Forged Rotating Assembly Kit [4.005] equal-distribution layout produces great midrange

equal-distribution layout produces great midrange torque without compromising top-end power

which allows these starters to work great while lasting a long time

Speedmaster brackets are constructed from durable steel

the LS-series heads are produced using our "Gravity Casting" process

The Speedmaster MidRise Air design features the identical plenum and runner design as the normal MidRise

Chevy LS2 4.000" 403ci Forged Rotating Assembly Kit [4.005] equal-distribution layout produces great midrangeSpeedmaster Chevy LS2 rotating assembly featuring a precision ground forged 4340 steel crankshaft, 4340 chromoly H beam connecting rods, and forged flat top pistons matched to your bore size.