Ok so let me start off with the bad technical info because I know how important it is and I know every one is going to ask these things but unfortunately I don't know these things yet only had the boat a few months, I have a 1975 Tahiti 17 foot it has a fresh 396 runs great, supposed to be running 9:1 with a mild cam and a 750 cfm quick fuel slayer carb with vac secondaries and fresh berk 12jc that's stock (I don't know what impeller or rpm I'm turning). I'm running what seems to be fairly wet and only pulls 47mph on GPS. I'm also at 5,400 feet above sea level. I've done a bunch of research and from what I find (not much being its a 396 and the guy said it dynoed at about 367 hp) my guess would be I should be closer to 60 +/- a couple? does that sound correct or should it only be doing 47? And like I said I'm sorry I don't have all the critical info you guys need to really know if I should be running a little faster I was more looking to see if any one could just kinda guess from they're personal experience. Also would a place diverter help at all gain anything other than being abel to fight fires and look good? Thank you guys very much!