Originally Posted by gfackrell
I followed the rebuilders recommendation and put a zinc additive in the oil for initial startup. I also ran the rpm to 2000 immediately on startup. Ran it like that for 5 or so minutes, then let it come down to idle and varied the rpm for the next 5 minues. Then to the lake, where I drove it at varying speeds for about an hour. For the next 5 or so hours I never pushed it hard, and tried to vary speeds.
It was supposed to be a stock replacement, and yes 275hp isn't very impresive, but I was/am on a budget. No other complaints really, it's just weak. It can only push the boat to 30 mph at 5200 rpm. The boat is empty, and light. I am hoping for 40 mph plus, and thought that a good 275 hp engine would do it.
The valve leakage needs to be addressed. But if you haven't set the timing up correctly, that alone can make a decent engine seem weak.
So do you happen to know what the initial timing and the total timing is, and at what rpm the mechanical timing is all in by? The distributor shouldn't have a vacuum advance, or if it's there it shouldn't be hooked to a vacuum source.