It'll probably be a little more with the LS6 heads he has, depending on how well they are ported. The L92 heads have great flow numbers on paper, and don't get me wrong, they are good heads for the price. But there are cathedral port heads that will make just as much power or more... Keep in mind those magazine articles only touched the tip of what has been done with LS engines. They tend to show builds with parts that they have been given by someone wanting the press. There is one particular late model GM magazine that seemed to be completely owned by one particular company. They always raived about this companies parts and their builds. Here in the real world, their parts were junk and they couldn't tune an LS1 to save thier life. Too many people ripped off because the magazines pockets were lined with that money.