how much hp?
 

anybody know, how much hp would an internally stock 4.6 mach motor be able to safely handle?

i think 480-520rwhp, i think, i know they strong engines
the manuals have a froged crank

bad question... the internals have no exact break point in power. They do have a real sensitivity to bad tunes though, so whatever you're going to do to it have it tuned really well.

I'd stop before 500hp. 460-480 would be quite a lot to ask of it on pump gas.

basically what im wanting to know is will it handle a blower, and how much psi

yes with a really solid tune. I'd keep it to 6-8 non-intercooled or no more than 9 -10 intercooled.

expect a LOT of hp gain and decent tq numbers. the mach motor is high compression and it makes ugly power from a little boost.

correct me if im wrong but i change boost level with different size pulley?

yes...

Here is Scott Hoag's (designer of the Bullitt and Mach 1) response to the same question asked on the mach 1 registry.

"Unfortunatly you are asking a theoretical question. Assuming the
rotating assembly is manufactured to nominal tolerances and the rotating
assembly is perfectly balanced and the calibration is flawless....you could
make tons of power....the final question is: how long will the engine make
this power?.....there in lies the performance paradox....no one can answer
this question, it will be what it will be.....welcome to the thrill and
excitement of building performance!"

Scott Hoag

you will need different tunes with different boost levels. its all in the tune most of the supercharged machs i seen are in the high 400's.