in this engine tech article HOT ROD compares the five best-selling Comp Cams camshafts for GM LS engines using a engine equipped with cylinder heads and either EFI or a 950 cfm carburetor - Hot Rod Magazine
In a compound turbocharger system, two turbos work in series, one after the other, to compress the incoming air, in contrast to a twin turbo system where two turbos in parallel share the work.