jeffery s bennett

The boat has been run with them both turning in, and out. It is faster turning in, and strangely seemed to handle better. The hop should be cured if you change to a high rake prop of the correct size. The boat would hop in most water conditions between 85 and 95, and only keep hopping up top if the water was very flat. The boat ran 110 with 700 hp per side, and was on the rev limiters. The engines were rebuilt and the heads changed, and the dyno showed 815. THE BOAT IS OUT OF PROP. I told the man that i sold the boat to the exact same thing. With a daughter in college and a divorce, i was not going to spend the money on props. The arneson needs a lot of rake to help lift the bow. I would consider changing the prop shafts to the mercury spline. They are the same diameter as a number 6 drive now, but not the same spline. If you change the shafts to a mercury spline, there are a lot more prop choices already in existence to try. The large nut that holds the ball into the socket is retained with three small clips, i installed the allen bolts with red locktite, and never had one loosen up. I would check them carefully when you reassemble the drive

shootitup

Thanks for answer jeffery s bennet !

good to know that the engine swap is useless.
Boat handles very good now when props turning in.
I have allready swap for #6 shafts. But it seems that eaven used 5 blade
18-20 rake props are 6000$. I only get 101mph with 25spline 33" rollas at 5500
before change shafts.
For now i have 4blade 35" #6 props.
With those 35" the top has been 104mph to limiters with huge 20% slip.
I need to over trim to get boat out of water.
There was fuel leak at other side tank when i bought the boat.
so i have cut the tanks to end to cockpit area (tanks are not at cabin area anymoore).
So that has change the CG i think, nothing else i havent done.
Boat keeps hoppin. I have try sand bags at bow and also at bilge.
Good 5blade high rake props could be the answer but those are too much for now.
For now i'am waiting Rik to send packaging and shims for drive.
We will do some extra locking for the nut, that it cant come out anymoore under any circumstances

When get the boat back to water i'll try my tunnel tab project.

jeffery s bennett

The Rollas ran to 110 on the limiters back when the hp was 700, it is strange that they would not do that with over 800, before you changed the shafts? I hope that the engines were not hurt before you bought the boat. I was upset with the person that i sold the boat to when he said that he pulled the chips out of the rev limiters and turned the engines to close to 6500 rpm in search of more speed. The engines were designed and built to run 6000 rpm max. Good luck with the tunnel tab, i would like to know how it goes

CIG3

Be very careful when you experiment with the tunnel tab. I could see how it could help to have a tunnel extension but dropping it down could have very negative results.

shootitup

Thanks for info Jeffery s bennet

Actually we ran with Rollas 101 at 5500 that was first summer and then i dont want to scream more rpm.
That was a good drive when somehow boat hops less.
After that i have try to solve boat hop feature.
I did not have a clue that rev limiter chips was pulled out, seller did not tell that to me.
What I have drove the limiters hits 6000, so chips were put back.
I have arrange good engine specialist to look the valve system before put it water.
I will cladly tell how the tunnel tab works when tested.

shootitup

I have test tunnel tab today with good results.

In Mirror smooth water the boat hop strongly.
When put tab downward the boat move bow down then trim props up and thats it no hop.
I try the hopping zone at 80, 90 and 90+ and yes boat stop hopping.
Now it is possible to drive mirror smooth water at 85-90mph without any kind of hop.
I was skeptical but it really work.

shootitup

[ATTACH=CONFIG]559310[/ATTACH]

jeff32

Everything ran fine after that modification? No regrets?

shootitup

Not big time experience. Found trim cyl leak that stops the season.
Trim cyl has gone broken same time when drive goes broken.
Trim cyl was cut off inside trim cyl yoke so cannot see that before.

I only drive few times and tested tab maybe 6 times. Every time it stops the hop.
Also manage tab up again and hop starts again and again tab down and hop stops again.

I see that when tab was down it need to trim up after that boat ran without hop eaven
mirror smooth water. Also notice that trimming up rollas start loose grip and rpm rise.

My CC is extreme heavy also CC has minor tunnel lift itself i cannot see
any danger values with that setup. Maybe cats with wider tunnel lighter setup and over 130mph.

I sold my 4blade rollas and now have 5blade herings waiting next season.

#6 shafts are on place trim cyl are repaired.

Herings must give whole different grip compare 4blade rollas.

Can say that am in fire for waiting next spring tests with tunnel tab and hering 5blade 18 rake

shootitup

easy +100mph cruising speed ~1000rpm still in stock