I have a 89 SUNBIRD ski boat with a 4.3 OMC Cobra O/D. My problem is I have been running a 4 blade Michigan Wheel Vortex 14.5 x 18. I can not pull a slolam skiier up very well so I went to a 15 x 16. This puts me very close to my upper WOT limit if not over. I still have trouble with the low end tourque pulling a slolam skiier up. The boat barely gets on plane under these conditions. (Usually 1-3 passengers and full fuel), I always thought it was just the way the boat was due to fact this boat sits so nose high at rest, meaning it seems to have the weight all in the rear. I have tried to move as much weight forward as possible and while skiing, we have passengers in the bow.
Now to my question. I have freind who has a 23 ft center console fishing boat with a Yamaha O/B. He was running a 3 blade SOLAS prop when he hit a log destroying the prop and damaging the lower unit. After repairs, he put on a VORTEX prop (same type I use). Its the same diameter and pitch with 3 blades as his previous prop. Strange thing is, he lost 9-10 MPH on top end turning the same RPM as the SOLAS prop. The speed was verified with GPS. He also said it seemed to be sluggish out the hole. The prop was checked and it had not slipped in the hub, and the diameter and pitch were correct as labeled .The guy at the prop shop who I use and trust said this could not be right unless the motor shop had put the wrong drive ratio gears back in the lower by accident. Long story short, he replaced the VORTEX with a SOLAS and evrything is back to normal. He is back to his normal top end speed and he claims the bottom end tourue is back. Is this possible?? Could it be that my prop is my problem too??
Now to my question. I have freind who has a 23 ft center console fishing boat with a Yamaha O/B. He was running a 3 blade SOLAS prop when he hit a log destroying the prop and damaging the lower unit. After repairs, he put on a VORTEX prop (same type I use). Its the same diameter and pitch with 3 blades as his previous prop. Strange thing is, he lost 9-10 MPH on top end turning the same RPM as the SOLAS prop. The speed was verified with GPS. He also said it seemed to be sluggish out the hole. The prop was checked and it had not slipped in the hub, and the diameter and pitch were correct as labeled .The guy at the prop shop who I use and trust said this could not be right unless the motor shop had put the wrong drive ratio gears back in the lower by accident. Long story short, he replaced the VORTEX with a SOLAS and evrything is back to normal. He is back to his normal top end speed and he claims the bottom end tourue is back. Is this possible?? Could it be that my prop is my problem too??
