| jaroot |
10-15-2003 11:00 AM |
case in point on the drive depth... IN A QUICK nutshell
my 16 donzi classic would chinewalk terribly in bone stock condition at 55 mph with an alpha GEN II and vengence prop due to various reasons... prop, excessive bow lift, lack of inner strake length for balance, rounded keel, length vs width, etc... props helped alleviate this.. cleavers and small diameter stuff mostly...
enter the alpha SS, raising the propshaft 3 inches (C/L of propshaft is 5 inches below keel)... 76 mph now (yes more hp too) and essentially runs on rails with the quad IV... and I will be pushing the limits even further very shortly.
the deeper the drive the larger the moment imparted on the hull... remember mr newton and his 3 lovely laws... shorten the drive and you shorten the lever arm and moment. if the hull has issues with balance then a high drive can help it maintain it's narrow operating window for balance.
skeg area also helps with stability but there are tradeoffs in terms of drag. the added chord length of the CLE gearcase was also a help in terms of tracking and steering...
my prop rotation is right hand, therefore my hull falls to the left chine... the hook in the chine accentuates the chinewalk... you can feel it begin and you can drive out by applying a rythmic steering pressure opposite to the direction of fall in sequence with the tendancy to fall to the chine.. or drive in a large sweeping arc opposite of fall which maintains pressure on the hull to hold it flat.
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