twin turbo 440

A lot of people will tell you that Maximum Boost by Corky Bell is the bible of turbocharging, but I found Street Turbocharging by Mark Warner to be easier to read and understand. Read either of these and you'll have a much better idea of how turbos work and what you'll need to reach your goals.

As for making 750-800 hp in a streetable twin-turbo 440 without an intercooler, good luck to you! I'm not saying it can't be done, but I wouldn't have the slightest clue how to make a street car with that kind of power survive without some way to cool all that turbo heat down. And if you keep the boost low (say 5 lbs.) to keep the temps down, why would you need a TWIN turbo?

My suggestion is to do some reading to help you put together an informed plan, then go from there.