What prop would perform best on this set-up with a 6" jackplate. I'm looking to buy a new one and was wondering what prop too get with it.
What prop would perform best on this set-up with a 6" jackplate. I'm looking to buy a new one and was wondering what prop too get with it.
My boat is loaded heavy. Ive got a 27T1 worked by Boger and a stock 25T1. They are both about the same. I really need 400 more rpms only running 5450 with both props. Best Ive seen is 73.4. If you need to try one before you buy let me know I can ship one to you. Buzz ran my 27T1 and think that is what hes running on his 200pro now.
Mark is indeed correct in my opinion. The 27 T-1 is a great prop once it's been touched by a prop craftsman. I jump back and forth between a 27 Power Tech TRO4 and the T-1.
I have that exact setup with the ox66 250hp yammie. I am running a stock T1 27p at 73mph gps with tournament load at 5600rpm. With moderate load I get 76mph at 5900rpm. If I have the prop tweaked, I am sure a couple more mph are possible with lower rpm. Hole shot is good and handling is easily controllable. I am sitting about 2 & 1/2 " below the pad. I started lower, but the chine walk was wicked. Moving up improved it a lot and did not affect water pressure, but I have to feather the throttle during holeshot when the bow breaks over because the prop slips heavily for about 2 seconds before hooking up. (any of you guys have a suggestiion?)
The boat had a 26p Mercury Tempest when I got it. 73mph gps with light load at 5700rpm. Boat handling was somewhat sluggish with moderate chine walk. The T1 really woke up this boat and made it exciting to drive. I have not been able to try the Powertech TR04, but several posts on this board have been very positive.
My boat used to break loose right at break over but the worked prop stopped it. The 25 T1 never done it. The boat came with a 29T1 and it was really bad about breaking loose and would only run 5200 rpm.
Get some numbers on the stock 27" T-1 and send it to Mark Croxton. You'll be glad you did. "Out of the box", the 27" TRO-4 is hot , but the worked T-1 is my favorite. It's a little faster and the ride is great for a 3 blade.
I had a 2004 with OX66 250 which turned a 27 Tempest 6200 and GPS'd 79.1.
I just sold a 2005 with 250 HPDI that would turn the same prop at 5850 and GPS'd at 77.1. This was a heavier boat with a 36 volt TM, Box between the seats, and 6 inch CMC hydraulic plate (heavier than the R&R manual).
Both boats were tournament loaded, about 20 gallons of fuel and no riders.
I have found the Merc to be at least 3/4 mph faster than anything else in the stock form.
We sell them here and we have the appropriate hub kits and or thrust washers to install with Yamaha.
Bill
Thanks for all the input guys. My dealer can only get a Merc or Yama prop, so I told him to set me up with a 27 pitch T-1. I'll break in the engine and see how it runs before I send it in to be worked.
Finally got my boat, and got 2 hours on the engine...... I tried a few short spurts at full throttle. I am running a 27 T-1....I got up to about 72 and she started to chine walk, but the speed was still going up. I looked at the tach and it was over 6000! I had 1/2 a tank of gas and half my equipment in the boat. I not sure how high my jackplate is set, but when I trimmed all the way out, I was getting a huge roostertail, but my water pressure was fine. Do I need to call my dealer and exchange my 27 for a 29?
Something doesn't seem right about that.
The 250 is a strong motor, but with the gearing it has, you should not be able to turn a 27 pitch to over 6,000. I don't think you'll be able to get out of the hole with a 29.
I may be wrong, but there is something else a miss. Your tach could very easily be off as well.
Jason Phillips
Either your jackplate is too high or you are running too much trim with a high jackplate setting. 6000rpm should put you in the upper 70's. Your prop is slipping too much (sucking air). Try running wide open at 3/4 trim. You should have 72-73 mph gps with little or no chine walk. Gradually trim up a bump at a time and watch your tach and water pressure. When you fail to gain speed with increased rpm, you are at maximum trim for your engine setting. Raising the engine cures most of the chine walk, but at some point you begin to lose leverage to raise the bow as the prop blades leave the water. You have the right prop. Get the engine height and trim correct, then make a judgement. Seat time my man!
I could only run full throttle for 1 minute spurts, so I didn't have alot of time to play around, but I did run full throttle and was bumping up the trim like you said. The speed was still increasing as I trimmed up, and I still had good water pressure...I was just over 6K on the tach. I'm thinking the jackplate is too high (due to the roostertail I was getting), but shouldn't the water pressure be below 20 lbs. if I'm too high?
Not necessarily. Yamahas like to run a little higher than most other outboards and the water pick-ups are a placed little lower on the lower unit.
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