Putting in a mopar crate engine?

i have a 1971 dodge demon with a 225 slant six and a 904 tranny in it i am putting a 8 3/4 rear end in it with 3.55 gears. i heard this will give the six enough power to satisfy me, i dont want to have a dragster but i want a car that will respond. will the new rear and gears be enough to increase the power or will i need to buy a mopar crate engine? if it does come to this then will it be very easy to install a 360/320 hp mopar crate motor v8? thanksPutting in a mopar crate engine?
the slant six is a good engine they will take a beating 3.55 sounds like OK but what are the oem gears if you are good with math you can take the diameter of the tire x 3.14 to find how many rev per mile the tire have and go from there if you have any sense you can... at cruising speeds 2800rpm to3000 at 60mph will give you power and be able to drive itPutting in a mopar crate engine?
oh i see you want more of "ha ha my cars woops azz" kinda car not "holy crap my car made it a quartyer miole in like 3 seconds dude!!!!!' well im not quite sure... sorry i cant helpPutting in a mopar crate engine?
It will still run like a slant six. If you want to put a crate engine in it, go with a hemi. I'm serious. For the money you would spend on a 360, you would be happier with the hemi.