one thing is did you get the spacers out of your K plane so your tabs will come all the way up. mine had the spacers in them and gained some mph after I had them taken out When my boat was stock it ran 67 to 69 mph after I put the pro chargers on it it ran 80 to 82 mph with 28 four blade bravo one props Now I do not have the pro chargers on any more do to the people that were working on my boat but that is a very long story and i'm now going in to all that right now
I ended up rebuilding both motors with all forged steel internals full roller and arp studs and bolts on everything and felpro head gaskets now I am ready for the pro chargers now So if you do the bottom ends make sure you have a very trust worthy shop to do the work for you and close by to check up on progress