New best for the Vyper this weekend
#5
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Joined: Aug 2010
Posts: 107
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From: Streamwood IL.
What props are you running? and what is your max rpm your running.
I have 28 props and the best rpms I can get is 4700 maybe 4750, and that's with trimming out the drives. 75-76 mph on GPS, I was thinking of getting different props, would like to hit 79-80.
I have 28 props and the best rpms I can get is 4700 maybe 4750, and that's with trimming out the drives. 75-76 mph on GPS, I was thinking of getting different props, would like to hit 79-80.
#6
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Joined: Jan 2005
Posts: 4,822
Likes: 376
From: IL
what I did with my 300 is I found were neutral position is in the tabs and outdrives,,you do this by placing a long 2x4 on the hull and slowly tap the trim tab button until its at the same angle as the 2x4(hull) I then did the same thing with the outdrive setting,,once I found the neutral spot for the tabs and outdrives I marked the gages so I always knew were neutral was and I knew never to make any turns with the outdrives lower then neutral,,(you just don't want to turn with the outdrives tucked in past neutral on a twin step boat)
so when I wanted to get the best performance out of the boat once I was on plane if the water was rough I would bring the trim tabs to neutral because all that does is extends the length of the hull and I would bring the outdrives to neutral setting as well and then I would slowly tap the outdrive trim button up until I got the rpms I wanted too,,and its not much higher off the neutral setting,,if the water was not rough I would leave the trim tabs all the way up..
you have to remember on a straight V bottom hull you want to trim up as much as possiable so you could get air under the Hull,,but in a step bottom boat you don't need to trim as much because you have all the air under the Hull you need from the steps..
hope this helps
Now I also just wanted to mention that this is all self taught things I do,,I have never taken any performance classes other than the auxiliary coast guard class I took 15 years ago,,
so when I wanted to get the best performance out of the boat once I was on plane if the water was rough I would bring the trim tabs to neutral because all that does is extends the length of the hull and I would bring the outdrives to neutral setting as well and then I would slowly tap the outdrive trim button up until I got the rpms I wanted too,,and its not much higher off the neutral setting,,if the water was not rough I would leave the trim tabs all the way up..
you have to remember on a straight V bottom hull you want to trim up as much as possiable so you could get air under the Hull,,but in a step bottom boat you don't need to trim as much because you have all the air under the Hull you need from the steps..
hope this helps
Now I also just wanted to mention that this is all self taught things I do,,I have never taken any performance classes other than the auxiliary coast guard class I took 15 years ago,,
Last edited by boatnt; 05-29-2013 at 12:29 PM.
#7
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Joined: Aug 2011
Posts: 1,696
Likes: 2
From: Metro Detroit
what I did with my 300 is I found were neutral position is in the tabs and outdrives,,you do this by placing a long 2x4 on the hull and slowly tap the trim tab button until its at the same angle as the 2x4(hull) I then did the same thing with the outdrive setting,,once I found the neutral spot for the tabs and outdrives I marked the gages so I always knew were neutral was and I knew never to make any turns with the outdrives lower then neutral,,(you just don't want to turn with the outdrives tucked in past neutral on a twin step boat)
so when I wanted to get the best performance out of the boat once I was on plane if the water was rough I would bring the trim tabs to neutral because all that does is extends the length of the hull and I would bring the outdrives to neutral setting as well and then I would slowly tap the outdrive trim button up until I got the rpms I wanted too,,and its not much higher off the neutral setting,,if the water was not rough I would leave the trim tabs all the way up..
you have to remember on a straight V bottom hull you want to trim up as much as possiable so you could get air under the Hull,,but in a step bottom boat you don't need to trim as much because you have all the air under the Hull you need from the steps..
hope this helps
Now I also just wanted to mention that this is all self taught things I do,,I have never taken any performance classes other than the auxiliary coast guard class I took 15 years ago,,
so when I wanted to get the best performance out of the boat once I was on plane if the water was rough I would bring the trim tabs to neutral because all that does is extends the length of the hull and I would bring the outdrives to neutral setting as well and then I would slowly tap the outdrive trim button up until I got the rpms I wanted too,,and its not much higher off the neutral setting,,if the water was not rough I would leave the trim tabs all the way up..
you have to remember on a straight V bottom hull you want to trim up as much as possiable so you could get air under the Hull,,but in a step bottom boat you don't need to trim as much because you have all the air under the Hull you need from the steps..
hope this helps
Now I also just wanted to mention that this is all self taught things I do,,I have never taken any performance classes other than the auxiliary coast guard class I took 15 years ago,,
I take Tres' class Saturday, I'll report back what I learned on this subject.
#8
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Joined: Aug 2010
Posts: 353
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From: WI
Wow guys I would have never thought about finding the neutral position but it makes perfect sense, I am going to find mine now. I know that even though we had/have the same boats and hulls there are going to be stacked up tolerances that make them different. ( I am talking specifically about the 300, I don't have viper money, Keith but I do have an adopted 380). We will find the neutral spot in the 380 as well. Thanks again probably one of the best things I have read, that you wrote, and you write a lot of great stuff.


