It does, because some turbos work best on a different engine size, how well it flows, and how strong it's built. A turbo from a PSD, I would guess, would be too much for the 302 or 351, since it's designed for a much bigger engine, with a far higher compression ratio. Generally, a large turbo will have a longer lag time and take longer to spool up, than a small turbo. There are plenty of V8 turbo sites, to check into. Myself, I'm looking into adding a couple smaller turbos, to a 460