Foxdoughnut

Hi there, over the winter I am planning on building a 370-400hp 13bt to go into an FC shell, I have heard through the grapevine that the stock engine dowls are only good for up to around the 350hp mark, can anyone confirm or deny this? and if so are there any reputable companys that make a/m dowls? also, are there any other weak parts of the engine that I should look at replacing to handle the extra power?
thanks in advance