Even though the Blacktop head incorporates a far more open up combustion chamber (see “Head combustion- chambers”) it still has a higher static compression ratio (see “compression ratio”), this is purely because of the piston design. The Silvertop piston encompasses a really small dome with two deeply angled exhaust flycuts, https://keeganpnmkh.blog2learn.com/79299699/everything-about-4age-20v