5.5m tornado 150 opti testing this weekend

[tom020780]

Ok so I have just re powered form twin 60 mercury's to a single opti 150 on a early tornado 5.5m and had initial run at low speeds, ironing out teething issues with external oil tank and some gauge issues running upto 25/30 knots. boat felt great very stable as usual in both relatively flat water and in some 2-3ft chop.

I am off testing this weekend to see how it performs a bit higher up the rev range and have been thinking about possibilities of chine walking. the hull is a medium v with a pretty large planning pad, engine has been set up 2 holes up and the boat is actually sitting with about 20mm more freeboard than with the twin 60's and engine weight is comparable although it has a little more grunt now.

I was wondering if a set of fixed tabs would be of any use if it does start to walk at a higher speed? I have read that they are useless unless on a longer water line boat but have also seen that a few people have experienced better stability at higher speeds with a set of fixed tabs?

Obviously I am going to know a lot more over the weekend but though I would learn a little more prior to going out.

[tom020780]

[tom020780]

[mitchc]

I've run almost exactly the same set up for about 4 years.
We used the RIB as a dive boat and when loaded up with 6 divers it performed perfectly with loads of grunt in all sorts of sea conditions.....
With just the me on board the boat was very hairy at top speed (over 45knts if you pushed it!) and would often chine walk pretty badly. I never let it get out of control, but on a flat sea I would imagine it could catch you out if you didn't keep on top of it.

Depends what you plan to use the rib for, but it will be fun with that lump on the back!
Enjoy

[tom020780]

Mitchc

Thanks for the reply good to hear other people's experiences

The rib is used for just about everything

Local back waters fishing and island hopping

Running 3 miles to a pub

Rescue boat

Days out

Towing inflatable and skiing

Maybe a bit more this year


Will find out about chine walking tomorrow I'm sure it's not that I need or want to do stupid speeds but the grunt to pull a wake board up or 2 will be nice but then again want to know limitations

Any thoughts on the tabs?

[mitchc]

Don't think trim tabs would stop chine walking?
If you need to trim the boat, for port/stb just move the crew around to balance the boat.....fore/aft use the trim button or again move the crew.

Hope you enjoy, remember the throttle goes both ways😜

[tom020780]

agreed throttle goes both ways....... will go have some fun and see what happens

boat popped up and sat strait up to 30 knots so will see what happens at a few more

[Bigmuz7]

Originally Posted by mitchc

Don't think trim tabs would stop chine walking?

No they certainly wont, not with that sort of power .. also because the spray rails on the Tornado hull are quite grippy (and the upper one inverted) you'll find the effect even more ... emm how can I put it ... frightening

I have two fixed stainless ones on mine which is a 5.4 The previous owner fitted them as it was used as a dive boat and gave the hull a bit more lift when loaded. I find that they make the hull behave more like a 5.8 - 6m hull, which is quite surprising given they are only about 6 - 8 inches long. Could also just be that its a good hull anyway one of the best Ive had IMO

Mind how you go now .. dont forget your kill cord when flight testing

[tom020780]

kill cord at the ready ............... hopefully I will update Monday

[Bigmuz7]

Originally Posted by tom020780

kill cord at the ready ...............

Good .. if its flat ..make sure its just you in the boat so you dont put the rest of your friends off boating for ever ...expect violence

[tom020780]

45 knotts WOT in clam this morning behaved impeccably no chine walking came up strait ......

Was more than a little surprised ...

I have to say I am massively impressed with this old tornado

21p prop could not tell what rpm it was running at as I forgot to change the switch over to 6 cylinder but did not sound high

But of slip in heavy load as ali prop on ATM will be interesting to see what the stainless one is like

Thanks for the advice people

Happy ribbing

[Iforb]

I think I'm going to have to polish my hull to get anywhere close to you with this new lump Tom!

It looks great on the water and sounds like it shifts pretty well already!