Why cant I bust 70mph?
#23
Charter Member # 55
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25lbs. of oil pressure is more than adequate at idle. Also, I agree with the others. Get rid of the Log exhaust. Going to even stock merc stuff through hull could add 2+ mph. You also need to get your rpms up to about 5000. The through hull will help, and also labbing the props will get it there.
#25
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Like Ron said FIRST: What are your RPM's? If you are way low on R's you may need smaller props, if too high and hitting rev limiter then you may need bigger props. Buying labbed props until you find the right pitch and diameter is a waste of money.
Once pitch and diameter are found try using a CLEAVER and mayber 4 or 5 blade props as well. All contribute to over performance and handling. Remember that to gain in one area you may likely lose in another. For example, you may lose dock side handling capabilities. Start with your RPM's and go from there.
Shane
Once pitch and diameter are found try using a CLEAVER and mayber 4 or 5 blade props as well. All contribute to over performance and handling. Remember that to gain in one area you may likely lose in another. For example, you may lose dock side handling capabilities. Start with your RPM's and go from there.
Shane
#26
Charter Member #232
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Nickslick this is sience that you are dealing with now. Seriously I am working on a place to stay out there for my next trip. Once I get all that figured out I will let you know when and then let me drive the boat and see what I can tell ya. We will get it out on a calm day or behind the break wall and see what we can do to get ya up were you want it to be. There may be some stuff we can do. First thing I would look at is get rid of the Log exhaust and go through hull. There were a couple of sets on EBAY that are worth a look at. I emailed you some info, and I know that there are lots of guys on the board that have them. I have one set I think that are good. I also have the remote Oil filter set up for the center riser. This you will love as it will get your filter up over the exhaust were it will be a piece of cake to get to. You can put that on your starboard motor so that you do not have to struggle to get the filter off any more. That has a Power steering and much larger oil cooler then you currently have. From there you can start to look at props if that does not help get the RPMS up. You should be looking for about another 200rpms out of that set up. However we have to make sure you are trimming it properly and all that good stuff.
Jon
Jon
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#27
Charter Member #232
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P.S. we had it going 68mph that day you and I had it out on GPS and I know you were not trimmed out all the way and it felt to me that the boat had a little over 70 in it so ......
Jon
Jon
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#28
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Nick,
Talk to my friend Steve. He has a Scarab 29 with small blocks running in the mid 80's.
Here is what his looks like. http://www.gcoffshore.com/gco_files/P29a.htm
I am sure he could point you in the right direction.
Dave
Talk to my friend Steve. He has a Scarab 29 with small blocks running in the mid 80's.
![Big Grin](/forums/images/smilies/biggrin.gif)
Here is what his looks like. http://www.gcoffshore.com/gco_files/P29a.htm
I am sure he could point you in the right direction.
Dave
#29
Charter Member #232
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Steve those new engines look great in your boat
WOW what a nice job you did. I am sure you are glad that they are in there
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#30
VIP Member
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Nick,
Do not wax the bottom!!! Get some different props and think about getting new exhaust.I lose 200 rpms at top end when I have my silent choice closed.Time to spend more money!!
BOAT=break out another thousand!!
Do not wax the bottom!!! Get some different props and think about getting new exhaust.I lose 200 rpms at top end when I have my silent choice closed.Time to spend more money!!
BOAT=break out another thousand!!
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Want your ECU tuned right?? Call Mark at Precision www.pmefi.com
Want your ECU tuned right?? Call Mark at Precision www.pmefi.com