How should it perform?

[GraAlaMat77]

I am looking to buy a 1992 Ranger 391V Commanche with a '92 Yamaha Pro V 200 on the back. Me and my dad took the boat out for a test run today. The motor cranked right up, idled perfectly, and sounded great. The boat has a 10" manual jackplate and I'm not sure of the prop. It is a 4 eared stainless steel prop. The guy who I am looking to buy the boat from has the jackplate set as low as it will go, because he is more concerned with a smooth ride and manueverability than with speed. I could not get the boat to hit 5000 rpm and the speed ended up at about 46-47 mph. Is the low speed and rpm due to the motor being set so low on the jack plate. He said he used to easily hit 5500 rpm before he lowered the motor. What should this boat be able to run with this motor?

 

[GraAlaMat77]

Re: How should it perform?

oh yeah, by the way, I have to make a decision and move on this boat fast before someone else scoops it up, anyone, any information?

 

[Silvertip]

Re: How should it perform?

Obviously with the motor lower in the water there is more drag and hence lower speed. Crank it up so the AV plate is at least even with the keel and preferably and inch or two above it. But don't go so high that water pressure is lost. This should allow the engine to get into its recommended wide open throttle band. If the engine is not in good mechanical shape (good compression, etc) it will not perform so there are other factors to consider.

 

[GraAlaMat77]

Re: How should it perform?

compression is good, engine is great, has been completely rebuilt prior to me buying it. How fast can I expect it to run?