10 M Rib with petrol inboards

the bandit · 06 February 2008, 18:00

I know there are quite a few 10 Metre ribs with outboards or diesel inboards. Does any one know of any 10m ribs with big inboard petrols. I am having one with twin 496 mercruisers rigged at the moment and wondered how it will perform

hobbit555 · 06 February 2008, 18:07

not usually allowed to be used commercially due to fire risk.

If it is all set up properly than should be ok.

hobbit555 · 06 February 2008, 18:08

glad I am not paying the fuel bill!!!!

the bandit · 06 February 2008, 18:20

Quote:

Originally Posted by hobbit555

not usually allowed to be used commercially due to fire risk.

If it is all set up properly than should be ok.

Sorry should of said its going to be used for pleasure and basic races.

Wondering if it will be the only one around with this set up.

codprawn · 06 February 2008, 18:28

I have always wondered why you don't see more like this - the petrol price I assume but big Yank engines should be quite cheap compared to diesel.

Bet it will go like stink!!!

Cookee · 07 February 2008, 11:05

I know the boat and it used to have a twin turbo Seatek in it, unfortunately it never performed to its potential - 496's are about 315hp if I remember correctly, so with 630hp, it won't be ultra quick although I would have thought it should break 70 ok - whether it breaks 80 will depend on the finished weight - what did Geof Hunton say?

Matt · 07 February 2008, 11:12

The 496 spec is 375, & the 496 HO at 425

Cookee · 07 February 2008, 11:22

Quote:

Originally Posted by Matt

The 496 spec is 375, & the 496 HO at 425

Thanks Matt - this senility is a pain in the arse! 750 for a pair of 496's unless they're HO's, assuming that the power is going through Bravo's, and correct C of G and the right props, it's got a chance of doing 80 something MPH I reckon - what do you think Matt?

ribit · 07 February 2008, 12:16

I voiced my opinions over on Boatmad as regards speeds achievable, however I know it's a bit late but If it were me I would of been tempted to try for a deal with either Evinrude on the new 300, Yam on the 350, or Merc on the coming Verado 350, for a loan of the motors, maintenance and fuel during the race, thereby saving my capital for the race and preparation in return for advertising an outboards ability on such a great adventure secondly as far as Verado is concerned it would make good advertising in the USA for their new engine should you pull off a good result with outboard power

codprawn · 07 February 2008, 16:41

Any info on the Verado 350 yet???

the bandit · 07 February 2008, 17:03

Quote:

Originally Posted by Cookee

I know the boat and it used to have a twin turbo Seatek in it, unfortunately it never performed to its potential - 496's are about 315hp if I remember correctly, so with 630hp, it won't be ultra quick although I would have thought it should break 70 ok - whether it breaks 80 will depend on the finished weight - what did Geof Hunton say?

with the utmost respect to you Cookee it ran with a single Seetek, so i understand it never ran properly as it had a split liner.

They are Ho engines i 425 rated and XR drives in the staggered set up.

Jono · 07 February 2008, 17:21

Quote:

Originally Posted by the bandit

with the utmost respect to you Cookee it ran with a single Seetek, so i understand it never ran properly as it had a split liner.

They are Ho engines i 425 rated and XR drives in the staggered set up.

With the utmost respect back at ya

... That's what Cookee boy said didn't he?

the bandit · 07 February 2008, 18:09

[

Quote:

QUOTE=Jono;237078] With the utmost respect back at ya

... That's what Cookee boy said didn't he?

[/QUOTE]

No He didn't

He said the original boat had twin Seetek's when it didn't

and the 496 were 315 HP when there 425 HP he may be thinking of the yanmar engines

jwalker · 07 February 2008, 18:15

Quote:

Originally Posted by Cookee

I know the boat and it used to have a twin turbo Seatek in it, ...

Which bit didn't you understand?

the bandit · 07 February 2008, 18:32

[

Quote:

QUOTE=jwalker;237087] Which bit didn't you understand?

[/QUOTE]

Miss read the twin turbo bit for twins. I beg for forgiveness. what i do know is the second turbo never worked thats why the boat didn't perform

He still got the HP rating wrong for 496 mercruisers. I will go back to boatmad.

Cookee · 11 February 2008, 11:32

Quote:

Originally Posted by the bandit

[

Miss read the twin turbo bit for twins. I beg for forgiveness. what i do know is the second turbo never worked thats why the boat didn't perform

He still got the HP rating wrong for 496 mercruisers. I will go back to boatmad. [/QUOTE]

No problem - it's easy to misread things - I did say I wasn't sure about the horsepower! Yes it had turbo issues and a split liner - I spoke to Jahn after he found out about that and he was gutted - do you know how he is now?

425 X 2 with staggered motors on XR's - it's getting better! I reckon you should go in excess of 80mph, possibly 85mph although full tanks would make a bit of a hole in that depending on how far back of forward the fuel is. Donzi ZR38 with the same engine and very light would go over 90mph on a good day, what sort of speeds are you expecting? With the staggered motors it should be well balanced for the rough water that everyone is expecting - need another crew member

Matt · 11 February 2008, 12:11

I absolutely would not, under any circumstances, race this boat around britain with outboards. There's isn't a single plus point to em on this hull and in the expected conditions.
IMVHO of course.

Quote:

Originally Posted by ribit

I voiced my opinions over on Boatmad as regards speeds achievable, however I know it's a bit late but If it were me I would of been tempted to try for a deal with either Evinrude on the new 300, Yam on the 350, or Merc on the coming Verado 350, for a loan of the motors, maintenance and fuel during the race, thereby saving my capital for the race and preparation in return for advertising an outboards ability on such a great adventure secondly as far as Verado is concerned it would make good advertising in the USA for their new engine should you pull off a good result with outboard power

the bandit · 11 February 2008, 15:34

[

Quote:

QUOTE=Cookee;237442] Miss read the twin turbo bit for twins. I beg for forgiveness. what i do know is the second turbo never worked thats why the boat didn't perform

]

Quote:

No problem - it's easy to misread things - I did say I wasn't sure about the horsepower! Yes it had turbo issues and a split liner - I spoke to Jahn after he found out about that and he was gutted - do you know how he is now?

425 X 2 with staggered motors on XR's - it's getting better! I reckon you should go in excess of 80mph, possibly 85mph although full tanks would make a bit of a hole in that depending on how far back of forward the fuel is. Donzi ZR38 with the same engine and very light would go over 90mph on a good day, what sort of speeds are you expecting? With the staggered motors it should be well balanced for the rough water that everyone is expecting - need another crew member

[/QUOTE

]

Must stop drinking wine in the afternoon

Never realised how much of the jolly juice we would need so basically its our secret weapon

Due to weight and set up when the boat is fully fueled i guss mid 70. It appears though reading various threads this may not change much as when light will have wrong props.

My question was aimed at running say 200 kg of fuel to with correct props.

ribit · 11 February 2008, 17:43

Quote:

Originally Posted by Matt

I absolutely would not, under any circumstances, race this boat around britain with outboards. There's isn't a single plus point to em on this hull and in the expected conditions.
IMVHO of course.

I said that because I thought in the RB in 84 the 2 phantom boats both with outboards achieved quite good results and I seem to recall reading about a rib that travelled around the Uk also with good results, and then of course their were the 2 young lads that went around Ireland I believe with outboard power.

Also the standard rib tested in boating mag's was said to be really good with the twin Verado's, although I realise that this Hunton was set up for a single Diesel inboard unit...but it was only a thought as Hunton 69 is already the proud owner of 2 big HP inboard petrol units for his challenge

Matt · 11 February 2008, 17:53

I refer you primarily to the honda motor saddles breaking in the honda series.
All the motors you suggested are consumer type models that are significantly heavier than the merc V6's on the 84 RB boats and which will likely suffer the same issues as the honda 225's. The saddles just aren't up to the job of racing. I think the yam V8 is a great motor, but it's saddle is piddly!

Secondly, the survivability of an inboard vs outboard in a dunking is significant. The V24's have been seen fully submerged, yet continued racing, an outboard couldn't survive the same.