Speed Pro Speed Pro Piston Forged 4.030" Bore 5/64 x 5/64 x 3/16" Ring Grooves - Minus 5.4 cc 205991 springs are precisely coiled and

springs are precisely coiled and undergo precision heat treating

Fan features a 60° blade design

Fits all Holley(R)

Tools / Cables / Accessories

630" ID - 5" Length - 120 lb 0500

Speed Pro Speed Pro Piston Forged 4.030" Bore 5/64 x 5/64 x 3/16" Ring Grooves - Minus 5.4 cc 205991 springs are precisely coiled andFully 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.