Despite the fact that the Blacktop head incorporates a extra open combustion chamber (see “Head combustion- chambers”) it continue to has a better static compression ratio (see “compression ratio”), this is solely due to piston design. The Silvertop piston contains a very tiny dome with two deeply angled exhaust flycuts, https://titusuadff.weblogco.com/31433714/a-review-of-4age-blacktop-engine-for-sale