there's no way I'd ever have a street engine below 9.5:1.... turbo or not, theyre too soggy to DD or do **** with. why do the 10.5-11:1 blower setups do so well? You cant run huge boost but theyre snappy, usually pretty reliable because they dont take a **** pile of boost to make power, easier on parts in general because the lower boost numbers. 8psi'ish is normally plenty etc... just think the build WAY out before you start buying parts.

 

x10000

my 11:1 408 with my "too small" tvs1900 was friggin awesome and tons of fun....and drove like stock with 600hp on tap.

 

You could just grab a 6.0 block, disregard the quench (hey, its turbo anyway) grab a good MLS gasket, get forged internals with forged pistons that move the ringlands down to handle the extra heat, buy some cathedral port heads that are around 230-240cc's moving around 320cfm @ .600 or better, keep the compression at 9.5:1, run a cam thats in the neighborhood of 240/254 on a 112 @ .050 and run whatever boost you want to hit your number. A motor like that would make close to 600 naturally aspirated on pump, and with a blower it wouldn't be hard to hit 900hp. Were only talking about 2.5hp per cubic inch. Thats not difficult with a dedicated turbo setup.

If you wanted more "low end" out of it, raise the compression to 10.5:1, and put another 15 degrees of duration in the cam to keep it from detonating in the lower rpm range on pump gas.