Proflow Cylinder Heads, LS3 SuperMax-B 260, Bare, Holden Commodore, Chev, Aluminium, 4-Bolt, LS3/L76/L77/L92/L98/LSX, 260cc Intake, 70cc Chamber, Pair - PFEAHCLS3-260-BAREPart Number: PFEAHCLS3 260 BARE LS3 SuperMax 260, Aluminium Cylinder Heads 15deg, Holden Chev, Bare Proflow does not sacrifice quality for a low price you get both with our aluminium cylinder heads. Our LS3 cylinder heads are designed for street race performance engines to give the ultimate in flow at a competitive price. Cast from A356 aluminium, these 15 LS3 rectangle port heads are designed to fit LS series engines with a 4. 00" or larger bore.