how much boost does the ford GT supercharger run?

I think it is between 8-10 psi....
High boost is dumb, its to hard on the engine....

That depends on static compression. (compression the engine has without the FI) High boost isnt "dumb". It just makes up for lack of atmosphere. Its dumb on most imports and a lot of euro cars because of the high compression ratios they run. It'll either end up floating the head, causing massive blow-by, or putting nifty holes in the head gasket. Or worse. Most american cars run relatively low compression ratios though and im sure the compression ratio on the GT isnt over 9.5:1 . Probably more like 9 even. If it is more then that its probably got a pretty stout bottom end. I believe the engine in the GT comes well equipped like the Cobra. 4 bolt mains, Manley H-beam rods and Forged pistons (probably dished). Plenty stout, and ready for some serious boost.

That depends on static compression. (compression the engine has without the FI) High boost isnt "dumb". It just makes up for lack of atmosphere. Its dumb on most imports and a lot of euro cars because of the high compression ratios they run. It'll either end up floating the head, causing massive blow-by, or putting nifty holes in the head gasket. Or worse. Most american cars run relatively low compression ratios though and im sure the compression ratio on the GT isnt over 9.5:1 . Probably more like 9 even. If it is more then that its probably got a pretty stout bottom end. I believe the engine in the GT comes well equipped like the Cobra. 4 bolt mains, Manley H-beam rods and Forged pistons (probably dished). Plenty stout, and ready for some serious boost.

I would be MUCH more impressed with the GT is it made its power without the blower....
And Ford runs lower compression ratios cause they supercharge lots of there cars and trucks to get power. GMs LS1, LS6 and new LS2 have 10.1:1 to 10.9:1 compression ratios.:-)