Looking at purchasing a boat equipped with a 502 mag that has a Vortec supercharger and intercooler installed. I have been trying to get a hold of someone at Vortec to see what the additional HP is with this add on. Apparently the only guy that knows anything about marine applications is on vacation till the 5th,WTF. It runs on pump fuel so Im guessing around a 100hp gain, Anyone with first hand numbers?