While the Blacktop head includes a much more open combustion chamber (see “Head combustion- chambers”) it still has an increased static compression ratio (see “compression ratio”), this is solely because of the piston design and style. The Silvertop piston incorporates a extremely smaller dome with two deeply angled exhaust flycuts, https://toyota4age48158.blue-blogs.com/38325192/5-essential-elements-for-blacktop-20v-4age