you can put up to 500 hp on a 2 bolt main. if your intensions are to only run it hard every now and then. if you are going to race it on a regular basis, you could run into some serious reliability problems. if you have enough money to get 450 hp out of a 327, then just sell your 327 and go with a 350 4 bolt block. you have so many more options with a 350. not to mention, you will have more hp with the same amount of cash spent.