We made a backing plate that completely mounts up for the Silvertop and Blacktop 4AG and enables the... Despite the fact that the Blacktop head includes a much more open up combustion chamber (see “Head combustion- chambers”) it even now has a better static compression ratio (see “compression ratio”), this https://cesargyqkb.techionblog.com/39986555/top-latest-five-blacktop-4age-urban-news