311Sr issues
 

Restored a 88 33sr. bravo boat. Raised drives x dimension 3 inches made small notch in transom and blue printed bottom, made vextra light weight eng. hatch. Put boat on a sever diet. added hp to engines aruond 440 each 9.5 comkpression 454 bored 60 over. roller cams mid 500 lift on both side holly 6800 d pump., aluminum imco exh. 26 pitch bravo spinning out only will make 4700 rpm at 67 mph. new stringer and bulk heads in cabin aftrr fiding rot in all of structure of the cabin. After all this work only 3 mph fatser from buying a 330 hp beat up bird. Too much time and money cant sell boat for what I am in to it.

What is your timing?
Have you tried turning the props in at all?

Something isn't right, I have the same power in my 292 and I'm hitting 69-70 on GPS. Other than the engines the drives and hull is 100% stock. I'm spinning 25 Hydro QIVs at 5000 RPMs.

What is a holley 6800 d pump? Your not saying its a 680 CFM double Pumper are you? If so thats part of your problem. I'm running HP 500 carbs on my engines which are 800 CFMs. 680's are WAY to small.