recent post of a youtube guy doubled the HP of a Chevy straight 6 with the wrong sized turbo and like 6psi? Ebay is full of uber cheap turbos now, and they all don't suck. Used a 'stock' Holley 2bbl carb and no timing mods! Keep it under 9 psi and you dont even have to boost reference the timing although you will want to boost ref the fuel pump (easy, plum a line from the bonnet to the fuel pump weep hole) all you need is: turbo, ducting, blow off valve, Peesh-pipe...sorry, 'J pipe' off manifold or similar hot side to turbo inlet, few feet of 1/8 tubing. Boost referencing the fuel pump ensure that the pumps stock 7 psi will not be overcome by the turbos 8 psi pushing into the fuel bowls blocking the 7psi of pump pressure to fill them. It should increase the pumps psi 1lb per psi of boost keeping the fuel pressure to +7 of the bowl vent pressure. Can't use an older smog Holley with a bowl vented outside the carb flange, plug it or tie it into the bonnet. Too big of a turbo will not spool up in time, you want a smaller turbo like from a 2.2 or a stock 4 cyl car: faster spool and no crazy boost levers for a low revving /6.
