Manley Valve - Exhaust, Valve-SBC S/D 1.500 1988-pontiac-firebird-esi5674963 One unique feature of UMI

One unique feature of UMI Performance's control arms is the on-car adjuster

precision machined piston with a deflective disc and a P

pinion angle

BMR Suspensions HCS760 Harness Crotch Strap is available in black hammertone and red powdercoat for long-lasting good looks

Lowering shackles are popular for adding additional rear lowering adjustment or leveling a factory height truck

Manley Valve - Exhaust, Valve-SBC S/D 1.500 1988-pontiac-firebird-esi5674963 One unique feature of UMIManley Severe Duty Valves deliver the ultimate in strength, reliability, and high performance durability. Engineered for extreme gasoline engine temperatures, these valves are crafted from exclusive materials (XH 428 for exhaust and NK 844 for intake), offering unmatched tensile strength compared to competitive alloys. In fatigue testing at 40,000 psi and 1400F, Manley exhaust valves endured 100 million cycles, while competitors failed after just