Non Stepped Kevlar Guns don't like shorter drives
07-06-2005, 12:35 PM
#1
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Non Stepped Kevlar Guns don't like shorter drives
We broke her in last weekend tried 28 to 32 pitch props and she hates the shorter drives!
With the 2" shorter drives all the the way out she now shoots a 250' rooster tail & nets us our best speed @ only 83gps and a good bit of our boat is still in the water, the same speed as my 600s with 1.5 ratios and smaller props, only now we run 1.35 ratios and bigger props with 800s and we can only net 5100rpms or so, way to much drag and slip ,we need to see 5600 to 5800rpms.
Per our research with a few old time Cig racing guy's, we are now going to lower her 1/2'' more than the stock Bravos with 2 1/2" Billet drive spacers and finally get her dialed in, I should have checked on drive hight with these hulls when we put her together and didnt do so, because almost all performance boats do better shorter.
I know some of you are stepping up the program on your Guns, so I will let you know how she likes the slightly deeper drives in a week or so!
With the 2" shorter drives all the the way out she now shoots a 250' rooster tail & nets us our best speed @ only 83gps and a good bit of our boat is still in the water, the same speed as my 600s with 1.5 ratios and smaller props, only now we run 1.35 ratios and bigger props with 800s and we can only net 5100rpms or so, way to much drag and slip ,we need to see 5600 to 5800rpms.
Per our research with a few old time Cig racing guy's, we are now going to lower her 1/2'' more than the stock Bravos with 2 1/2" Billet drive spacers and finally get her dialed in, I should have checked on drive hight with these hulls when we put her together and didnt do so, because almost all performance boats do better shorter.
I know some of you are stepping up the program on your Guns, so I will let you know how she likes the slightly deeper drives in a week or so!
07-06-2005, 12:41 PM
#2
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Re: Non Stepped Kevlar Guns don't like shorter drives
I think that if you are going to run them high, boxes would help greatly.
What kind of drives are those?
Where is the bullet in relation to the hull bottom?
Craig
What kind of drives are those?
Where is the bullet in relation to the hull bottom?
Craig
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Happily retired and living in Heavens waiting room.
07-06-2005, 01:48 PM
#3
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Re: Non Stepped Kevlar Guns don't like shorter drives
Originally Posted by WildWarrior
We broke her in last weekend tried 28 to 32 pitch props and she hates the shorter drives!
With the 2" shorter drives all the the way out she now shoots a 250' rooster tail & nets us our best speed @ only 83gps and a good bit of our boat is still in the water, the same speed as my 600s with 1.5 ratios and smaller props, only now we run 1.35 ratios and bigger props with 800s and we can only net 5100rpms or so, way to much drag and slip ,we need to see 5600 to 5800rpms.
Per our research with a few old time Cig racing guy's, we are now going to lower her 1/2'' more than the stock Bravos with 2 1/2" Billet drive spacers and finally get her dialed in, I should have checked on drive hight with these hulls when we put her together and didnt do so, because almost all performance boats do better shorter.
I know some of you are stepping up the program on your Guns, so I will let you know how she likes the slightly deeper drives in a week or so!
With the 2" shorter drives all the the way out she now shoots a 250' rooster tail & nets us our best speed @ only 83gps and a good bit of our boat is still in the water, the same speed as my 600s with 1.5 ratios and smaller props, only now we run 1.35 ratios and bigger props with 800s and we can only net 5100rpms or so, way to much drag and slip ,we need to see 5600 to 5800rpms.
Per our research with a few old time Cig racing guy's, we are now going to lower her 1/2'' more than the stock Bravos with 2 1/2" Billet drive spacers and finally get her dialed in, I should have checked on drive hight with these hulls when we put her together and didnt do so, because almost all performance boats do better shorter.
I know some of you are stepping up the program on your Guns, so I will let you know how she likes the slightly deeper drives in a week or so!
07-06-2005, 02:02 PM
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Re: Non Stepped Kevlar Guns don't like shorter drives
I am running one inch shorties and not having any issues. I inquired about going -2 inches and JT said NO. Thant was enough for me.
Last edited by expresscat39; 07-09-2005 at 12:07 PM.
07-06-2005, 02:05 PM
#5
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Re: Non Stepped Kevlar Guns don't like shorter drives
Originally Posted by OldSchool
I think that if you are going to run them high, boxes would help greatly.
What kind of drives are those?
Where is the bullet in relation to the hull bottom?
Craig
What kind of drives are those?
Where is the bullet in relation to the hull bottom?
Craig
The bullets are higher than the bottom of my hull, I don't know how much!
She requires more tab than before at any speed bellow 65 mph and insane amounts of trim but only at speed , drives all the way in until we loose our tabs @ speed.
The drives aren't low enough to lift her up and out of the water there's just not near enough leverage.
With the drives completely out @ 80+ she isn't loose at all , almost like a barge ,before if you set the drives out past position 5 or so she was real loose and would chine walk like hell over 75mph.
07-09-2005, 01:52 AM
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Re: Non Stepped Kevlar Guns don't like shorter drives
I had a '94 TG (full pleasure straight hull) that originally came with SSM 3's and I decided to try some SSM 4's (direct bolt on) to see what would happen when I brought the drive height up. Didn't work. Barely got on plane, ran like c**p, and gained no speed. High drive heights do not automatically equate to speed and overall performance.
