Re: HP rating
Is this a 72 390? If so it had a stock HP rating of 201hp with 8.2:1 comp ratio. Are you still running the stock cam? What Edelbrock intake did you use? Performer or RPM? What size primary tube on the headers and exhaust pipe size?? The Performer intake is pretty much the same as the factory 4V intake. The main thing here is the weight savings. If I had to take a wild guess I'd say 250-275hp. But depends more so on the exact parts used in the build. More info is needed.