Re: Anyone with a 2700 SC/SCR and a singe 350/5.7?
I don't know that I would focus on speed regarding this, but rather RPM's. You should, theoretically be able to reach close to the MAx RPM recommended for that engine. The general (non-scientific) rule of thumb is, At Wot (Wide Open Throttle) if you are below the Max RPM range, then you're over-propped. If you're over the MAx RPM range, then you're under-propped. Neither is terribly good and can potentially harm the engine. I like to use the 50-75 percentile as an average. So if the boat MAx RPM range is 4200 -4800, then If I'm hitting 4650 at WoT, then I'm pretty good. Technically, I'd probably be happy with 4500 RPM.
Speed can be influenced by sea size/state/direction, wind, current and tides. You'll technically be going slower Kph/Mph going into a head sea or wind, then with non or a following sea for example.
I would also make sure that trim tabs are all the way up and then start slowing trimming up the outdrive watching the RPM change after each click. You will eventually hit a sweet spot. That should at least give you aball park. Consider calling US Marine. They should be able to tell you what the stock prop setup was on that year make and model a can even look at similar models from other years. Let's face it, the featrues and asthetics change from year to year, but the length, width and weight of the boat don't change THAT dramatically.
|