i build many bbc for street/ strip and any thing you can put one in . i have over 20 bbc core blocks to build from in stock at my machine shop . there many 396 /402 pistons to pick from if you use the open chamber head the KB icon line is a good way to go .you really can not bore a 396 to 4.250 less a very early block and that will only get you to a 427 .less you use a4.000 454 crank. far better to start with a 454 block and crank if you want a 454