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klaw
11-19-2008, 04:14 PM
for a bravo how far below keel is everyone putting the prop shaft or how far from keel to centerline of crankshaft (x-dim)

I am putting together a drawing showing blackhawk, blackhawk on extension box bravo, bravo shorty, and bravo on extension box reg and shorty and will share with everyone when its tabulated

Offshoredrillin
11-19-2008, 06:38 PM
everything that you have mentioned is going to change the X on all of them, a box is 12 inches, and angled up, good thing for a blackhawk, an ITS is a straight 8 inches back, so the x must go up to compensate. From what I have been told and seems to be the rule, the bullet on the BH should be even or about a half inch higher than the keel. if it is too high you will blow the prop out.

klaw
11-19-2008, 07:26 PM
yes I know
So far I have a std bravo and a standard Black hawk drawn to scale I also have the cig hull to scale and am messing with them I also have a exyension box to scale and a 3 inchshorty
I did this by doing pdf to dwg conversions and the scaling up to be the corect size dimensionally

I am doing this to see if I can pick a location where I could hot swap a bravo to a blackhawk to change boat from a easy ski run about to a hot rod

May be barking up a wrong tree but when I am done will have a nice library of scale out drive drawings

klaw
11-19-2008, 07:27 PM
everything that you have mentioned is going to change the X on all of them, a box is 12 inches, and angled up, good thing for a blackhawk, an ITS is a straight 8 inches back, so the x must go up to compensate. From what I have been told and seems to be the rule, the bullet on the BH should be even or about a half inch higher than the keel. if it is too high you will blow the prop out.

Is the 1/2 inch with th cavitation plate parralel to th bottom
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Offshoredrillin
11-20-2008, 09:15 AM
no, for the blackhawk it should look like this ___|< the bullet should be right at or about halh inch up. the cav plate on a BH is angled as well, not like a reg bravo. here is a pic of two standard xrs and a blackhawk on a box

Offshoredrillin
11-20-2008, 09:18 AM
and here are a couple blackhawks..the red one is marc bermans on an ITS

klaw
11-20-2008, 10:48 AM
thanks for the pics Rob

Could be the angle of the pic but they sure look higher the 1/2 inch up from the keel

Offshoredrillin
11-20-2008, 11:25 AM
thanks for the pics Rob

Could be the angle of the pic but they sure look higher the 1/2 inch up from the keel
the one with the box is, thats a newer hull with pad, you can see it's flat, the other is marc and ricks, they both have the older round bottom with rocker like ours...I think the magic number is going to be right around 17, we will figure it out and dave will cut mine.