I just wanted to get the opinion of some of the experienced engine builders on this site. I have been searching through many of the old threads looking for information on how many HP stock pistons will stand up to. Looking thru most of the treads it appears that it is the rods that fail and not the pistons. Knowing that peak pressure does not change much on turbo engines I was wondering how much HP a set of stk pistons with aftermarket rods would hold up to? My thought was to try and get my D15B7 up around 300hp. I wanted to stay away from Vitra pistons because of the low compression even with custom length rods. The engine would be a dog out of boost. I am looking to build an efficient daily driver with the added excitement of boost. I would like to avoid the expense of forged pistons If I can. I was thinking that Vitra pistons are not forged and have a pretty thin top land. What makes them stand up to 450HP and why wouldn’t I be able to get about 300HP out of factory?