Holden 253 304 308 12 Point Black Oxide Intake Manifold Bolt Kit strength and horsepower capabilities are

strength and horsepower capabilities are significantly outstanding compared to cast forged crankshafts

Speedmaster aluminum valve covers feature a classic raised

open screen design

They are manufactured from cast aluminum and are offered with breather holes or without any holes

Holden 253 304 308 12 Point Black Oxide Intake Manifold Bolt Kit strength and horsepower capabilities areSpeedmaster black oxide coated chromoly intake manifold bolts are rated at 170,000 psi. They're precision machined for optimum thread engagement and have a wide area flange for better load distribution. They also feature precision rolled threads, which prevent galling, while promoting more consistent torque loading.