BAD BEHAVIORS NEW PROP, MORE INFO PLEASE

[BAD BEHAVIOR]

Ok, I finally got to take the new prop out and run her proper. If you guys remember Im now running a 20" four blade powertech prop. The first time I ran it, I could only get about 3/4 throttle b/c of the waves. Sunday, I took her out and really got on her. The only problem I have is I can only run 3/4 throttle w/o the rev limiter buzzer coming on. My first thought says get a bigger prop. I talked with the folks @ powertech and they say for my boat, this is the prop, that I must be over trimming. Not possible. I only trim it up about 30 percent. My rooster tail is only about as high as the base of my cowling. My jack plate is al the way down. Ive had my tach checked. According to their computer models, I should be getting 62-65 mph yet I can only get around 54. Not that thats a bad speed but I should be able to run WOT if I wish to. Powertech says I will lose alot of holeshot if I go up in pitch but I dont know what else to do. I swear my boats are like my woman, Everytime I think Ive got her tuned in, she throws another hitch in the line!!!! No damn wonder Im single!!! Any suggestions would be appreciated as usual.

[tin can]

In your previous thread you stated you raised the motor two holes, before you changed props. That's when you started blowing out. Lower the motor all the way back down and see what happens.

[RD]

Is the new prop cupped? if not send it to Gator and have them cup it,gives it a little more bite

[What a mess]

Is the new prop cupped? if not send it to Gator and have them cup it,gives it a little more bite

I had the same problem, I went to gator and added some cup.

He is awesome it is on the road just past the Perry airport headed to Spring Warrior if your headed into Perry from Shady Grove just go straight across at the Hardees the sign is old you have to look for it its on the right a little shop next to a house.

I could care less what the computer says the boat knows and you can't fool it. Look less at the speed and more at the tach if you are running correct rpms at full throttle according to your engine specs cool if you are over revving the motor that needs to be changed.

Also if your hole shot is good the boat ill tell you what top speed should be.

[BAD BEHAVIOR]

I dont know if you guys saw the pictures from the last thread, but it has a ton of cup. And TC, the motor doesnt seem to be blowing out or what I would call blowing out. I agree that I may have to lower it but that was the whole reason for even buying the new prop was to allow me to raise my motor as to be able to get in skinnier water. I also agree with W_A_M in that the boat knows more than the computer and I am not particularly worried about top speed as I am running WOT. I wonder if I should try the bigger prop, and how much hole shot Ill be losing? Shes really fast out of the hole now, I mean really fast. Thats very good in shallow water, provided there aint no rocks!!

[Barhopr]

What happens to the water preasure when you go from 3/4 throttle to WOT and a overrev alarm? If your running with the plate up high you may have to trim the motor all the way in to maintain preasure and to keep from over-reving the engine.

[BAD BEHAVIOR]

Water pressure gauge maintains pressure at over rev. Jack plate is all the way down. Thats the part I dont agree with with Powertech. I still think I need to be running a 21 or 22 pitch. I just wonder how much hole shot Ill lose. I know that with the bigger prop, she'll run like a scalded dog, but Im more interested in being able to go skinny with my boat. I want to be able to take off in <2ft like I can now. I also want to be able to run WOT without blowing up the Opti.

[Seachaser]

I may be missing something, but on my boat with the jackplate, I have a tough time with 30% trim. These are just my observations and just from my boat:
A - I lose top end speed by both raising my motor and by going with a four blade prop.
B - With the jackplate, the higher I go the less I nee to use the trim.
C- I am perfectly happy with the performance, and if I had wanted to go faster, I would have left the jack plate off.

[Tom Keels]

You said the rev limiter comes on but what is your actual RPMS when you hear the rev limiter?

[What a mess]

Big wheels keep on turning. (I see a bigger prop in your future)

If I had the $50k to spend on a boat I would want it right too.

Don't try to figure it out on your own.

I would go to a pro rigger prop guy some one that does this daily.

He would go to the pond with a half dozen props and swap till you got what you wanted.

Listen to the boat it knows itself better than you do.

What does the mfg say?

[Chalk]

I only trim it up about 30 percent. My rooster tail is only about as high as the base of my cowling.

Dam...Why so much trim? If you jack up, you need to trim back down...If you can jack up 5 inches you should be using very little trim...

IAccording to their computer models, I should be getting 62-65 mph yet I can only get around 54.

It doesn't take into account that you have a sail on top of your boat...if you didn't have a T top it would probably do close to what the computer says.

[BAD BEHAVIOR]

I may be missing something, but on my boat with the jackplate, I have a tough time with 30% trim. These are just my observations and just from my boat:
A - I lose top end speed by both raising my motor and by going with a four blade prop.
B - With the jackplate, the higher I go the less I nee to use the trim.
C- I am perfectly happy with the performance, and if I had wanted to go faster, I would have left the jack plate off.

Good points, but I really dont give a dang about top end speed. What it does it does. i just want to get the optimum performance from the boat, which is a lot more than just top end speed. Thanks for the input, it helps to look @ the problem from more than one view.

[BAD BEHAVIOR]

You said the rev limiter comes on but what is your actual RPMS when you hear the rev limiter?

Rev limiter comes on between 59 and 61. I had the tach checked to be sure it was accurate.

[BAD BEHAVIOR]

Big wheels keep on turning. (I see a bigger prop in your future)

If I had the $50k to spend on a boat I would want it right too.

Don't try to figure it out on your own.

I would go to a pro rigger prop guy some one that does this daily.

He would go to the pond with a half dozen props and swap till you got what you wanted.

Listen to the boat it knows itself better than you do.

What does the mfg say?

Thats why I chose powertech for my custom prop. Im just trying to get some input from folks who I know have been on the water a long time. Powertech did just that today. They have a 220lts that is one of their test boats( they do a lot with the redfish tourney guys). They went to test today and are supposed to get with me tomorrow.

[BAD BEHAVIOR]

I only trim it up about 30 percent. My rooster tail is only about as high as the base of my cowling.

Dam...Why so much trim? If you jack up, you need to trim back down...If you can jack up 5 inches you should be using very little trim...

IAccording to their computer models, I should be getting 62-65 mph yet I can only get around 54.

It doesn't take into account that you have a sail on top of your boat...if you didn't have a T top it would probably do close to what the computer says.

At 25-30% trim , My boat seems the most stable. Thats with the tabs up. I ve been testing , playing with the jackplate, but when I run 55-57 rpm,about 3/4 throttle, Im running the jack all the way down to ensure not blowing the prop out. Powertech doesnt seem to think Im losing bite to air, they are leaning towards a prop with a little more pitch. We've been talking about a 21-22" prop. Marcus @ Powertech says that some motors from the factory are a little hotter than the others. He said it also has to do with the way it was broken in. I didnt run WOT until I had 20 hours on it. I did run it in blasts but never more than a few seconds. He said that allowed really tight seals so my motor was probably running more efficent than one that was not broken in as gingerly. 5700 rpm should be the peak, not 3/4 . Im looking forward to this weekend when I can run her again!!! Also, what do you guys consider a good hole shot? Powertech tells me three boat lengths but that seems a little slow to me.