Speed Pro Speed Pro Piston Forged 4.040" Bore 5/64 x 5/64 x 3/16" Ring Grooves - Minus 6.1 cc RRP2EX Base will not work with

Base will not work with Holley 4bbl

Z34 Front Calipers

1970-1974 GMC P25/P2500 Van

(1) #6 Fuel Return and (1) #6 Rollover Vent Valve

Speed Pro Speed Pro Piston Forged 4.040" Bore 5/64 x 5/64 x 3/16" Ring Grooves - Minus 6.1 cc RRP2EX Base will not work withFully updated skirt profiles Exclusive DUROSHIELD skirt coating. DUROSHIELD provides scuff resistance, reduced bore clearances and enhanced ring sealing. SPEED PRO POWERFORGED pistons are built to stringent specifications with a precision CNC machined dome and skirts and microfinished ring grooves. The manufacturing process ensures that piston weights within a boxed set will not vary more than 4 grams and that skirt sizes are matched to within 0.