Success!! Well... mostly.
06-09-2002, 09:41 PM
#1
Platinum Member
Platinum MemberThread Starter
iTrader: (2)
Success!! Well... mostly.
Finally, I have a working boat to use this summer! Someone even commented to me on how beautiful the boat is and that it belongs out on the Bay rather than stuck in the nasty old Potomac.
Anyway, the old girl did extremely well, despite some small complaints, on her first outting of the season. I managed to crank her up to a whopping 40 MPH on GPS. But before anyone says anything let me explain. First, I have to remove a half tank's worth of old fuel. I mixed in some 92 octane and set the timing at 32* at full advance. With a load, she would ping. Now, that 40 MPH was done with NO load. I was turning 4100 RPM without the secondaries open. If I tried to open the secondaries, I'd get detonation. Not good. I figure that it'll take a couple of trips to remove the crap gasoline and then all should be better on that front. Second, the 21P prop is too small (based on the above criteria). I'm thinking that I'm in the same boat (pardon the pun) as the rest of us high output small block guys. The jump in power has really made the lower pitch props useless in the application (and suggestions based on prop calculators and Merc have yet to be useful as well). I'm thinking that a 23P or 25P would do the job. I guess I'll have to experiment and see. Third (and this has nothing to do with speed or performance), the boat is just too loud. The wet exhaust does help but I really do need to get some mufflers on there or somehow direct the exhaust down into the water (it was so nice backing the boat up and having the water cover the pipes, nice and quiet for the moment). At cruise it isn't too bad, but at idle and no-wake speeds the drone is over-powering.
All in all it was a great day. Word to the wise though, do not try and out in a Gravely Point (for us Potomac River boaters) on the weekend! It took me nearly an hour and a half to get launched since there were a bunch of idiots trying to get their boats in and out. A total mess!
Great day folks!
Tom
Anyway, the old girl did extremely well, despite some small complaints, on her first outting of the season. I managed to crank her up to a whopping 40 MPH on GPS. But before anyone says anything let me explain. First, I have to remove a half tank's worth of old fuel. I mixed in some 92 octane and set the timing at 32* at full advance. With a load, she would ping. Now, that 40 MPH was done with NO load. I was turning 4100 RPM without the secondaries open. If I tried to open the secondaries, I'd get detonation. Not good. I figure that it'll take a couple of trips to remove the crap gasoline and then all should be better on that front. Second, the 21P prop is too small (based on the above criteria). I'm thinking that I'm in the same boat (pardon the pun) as the rest of us high output small block guys. The jump in power has really made the lower pitch props useless in the application (and suggestions based on prop calculators and Merc have yet to be useful as well). I'm thinking that a 23P or 25P would do the job. I guess I'll have to experiment and see. Third (and this has nothing to do with speed or performance), the boat is just too loud. The wet exhaust does help but I really do need to get some mufflers on there or somehow direct the exhaust down into the water (it was so nice backing the boat up and having the water cover the pipes, nice and quiet for the moment). At cruise it isn't too bad, but at idle and no-wake speeds the drone is over-powering.
All in all it was a great day. Word to the wise though, do not try and out in a Gravely Point (for us Potomac River boaters) on the weekend! It took me nearly an hour and a half to get launched since there were a bunch of idiots trying to get their boats in and out. A total mess!
Great day folks!
Tom
Last edited by TomZ; 06-09-2002 at 11:21 PM.
06-09-2002, 11:17 PM
#3
Platinum Member
Platinum MemberThread Starter
iTrader: (2)
Yeah, I know. One good think is that the Vortec heads allow a higer compression ratio to be safely run. 10:1 and 92/93 will more than likely suffice. The way I boat will seldom require a stop at a dock filling station, however, if I need to fill up and cannot get super then I will run it accordingly. I ran just about the same amount of compression last year (even though the motor lasted only a short while) and there was no hint of detonation. I don't think detonation will be a big issue but I'll be keeping my eyes (and ears) on it.
Later,
Tom
Later,
Tom
Last edited by TomZ; 06-09-2002 at 11:22 PM.
