How fast will it go?
04-23-2003 | 01:53 PM
#32
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From: Kentucky - where the women are so fast we have to put a governor on 'em!!
The original engine was a 7.4L , 330 crankshaft hp.
Just curious, what kind of speed and RPM were you getting with the 330? What prop were you running? I have the same exact boat, but mine started life as a small block/Alpha. Changed over to a warmed over 454/Bravo. Currently getting around 60, expected more.
04-24-2003 | 05:21 PM
#33
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From: Westport, Kentucky
Tested today with a 27 Mirage Plus. Spun it about 5400. Speed was 79 upriver in a 2 to 3 MPH current and glass smooth water. RPM was high due to having to give it a little more trim to get the bow up. Lots of prop slip up top due to excess trim.
Boat was very stable at this speed, no hint of chine walk or anything. I think my hooks need to come off. The faster you go it just feels like the hull is planting the nose more, way too much boat in the water. Overall I am very satisfied.
I worked out the block pressure problem with a 3/4 pressure relief valve. I have it now where the pressure is 18 at cruise and around 20 at WOT. Engine temp at WOT was about 155 and 140 at cruise. Oil got up to 240 at WOT.
Overall a successful project so far.
Tim T.
Boat was very stable at this speed, no hint of chine walk or anything. I think my hooks need to come off. The faster you go it just feels like the hull is planting the nose more, way too much boat in the water. Overall I am very satisfied.
I worked out the block pressure problem with a 3/4 pressure relief valve. I have it now where the pressure is 18 at cruise and around 20 at WOT. Engine temp at WOT was about 155 and 140 at cruise. Oil got up to 240 at WOT.
Overall a successful project so far.
Tim T.
04-24-2003 | 06:43 PM
#34
Ginger or Mary Ann?
Joined: Oct 2000
Posts: 11,030
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From: L
Surely you can squeeze a bit more of it. 
Push down harder!!
I ran 83mph with a 27 Hydro. I think right at 5500? With my boat a 27 Fountain, actual running length was probably real close to what you have. Weight was 4950, according to factory spec sheet.
Glad to hear you got it all dialed in with temps and pressure.
Now, how was the throtle response?
Push down harder!!I ran 83mph with a 27 Hydro. I think right at 5500? With my boat a 27 Fountain, actual running length was probably real close to what you have. Weight was 4950, according to factory spec sheet.
Glad to hear you got it all dialed in with temps and pressure.
Now, how was the throtle response?
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Some people are like Slinkies - Not really good for anything, but they
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Some people are like Slinkies - Not really good for anything, but they
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04-25-2003 | 07:20 AM
#36
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From: LaPorte IN.
Nice speeds!
Sounds like it is going pretty well so far. Don't forget to do some plug readings especially on a new motor. Let me know if removing the "baja hooks" helps. I am searching for a couple of MPH to get me into triple digits and that was something I considered. Many differing opinions on pros and cons of removing those hooks. At speed over 70 on my boat the hooks are out of the water and really only seeing spray or "soft water" as I have heard it termed so the speed gains may only be minimal. I have consulted with Baja about these hooks and they agreed that the speed gains would be there, but probably minimal and warned me that the boat may tend to porpoise at cruising speeds and the hole shot may suffer. I am not about to put tabs on a 21' boat so it may not be an option for me. Good luck and be sure to post any results you come up with on the hooks.
