New / Spare Prop

[brucehawsker]

Running 21" Laser on my 150 opti and 6.5M Solent. Want to up my WOT speed - yes, I'm a sad bugger. Don't pull anything. This is about the need for speed. No real need to be fast out of the hole - wife tells me off when I do anyway. But when near WOT she is hanging on and the Opti 'deafens' me!!!!

Currently about 45/46K on gentle chop with 1/4 tank and 2 adults. Ideas please?

Thanks as ever

[Pete7]

Bruce, you need to know what the max revs are at your current top speed, but I recon your pretty close to the biggest prop you can turn now.

If you want to go faster you need a bigger engine or loose some weight, out of the boat that is.

Pete

[Hightower]

Originally Posted by Pete7

If you want to go faster you need a bigger engine or loose some weight, out of the boat that is.

Pete

Loose the Wife and run on fumes, take that horse shoe life ring off the back (should decrease your drag a little) and off you go

Be sure to let us all know how you get on.

[brucehawsker]

I need to lose weight personally anyway

[Downhilldai]

Originally Posted by brucehawsker

..... But when near WOT she is hanging on and the Opti 'deafens' me!!!!

Surely, you don't expect more speed and less noise?

If you want less 'deafening noise', better get rid of the Opti.

[Mollers]

I find the 'prop advice' on this site so hit and miss that it's close to no use at all. I have the same engine and the same prop as yourself on a 6.5m Vipermax. I get 40knots and that's the lot, I'm surprised that you're getting 6knts more. No way could I run a 23P prop, it would kill the boat. I'd struggle to get on the plane.

[Hightower]

Originally Posted by Mollers

I find the 'prop advice' on this site so hit and miss that it's close to no use at all. I have the same engine and the same prop as yourself on a 6.5m Vipermax. I get 40knots and that's the lot, I'm surprised that you're getting 6knts more. No way could I run a 23P prop, it would kill the boat. I'd struggle to get on the plane.

They're completely different shapes of Hull, the 6.5m Solent in nearer 7m in length BTW, but has a much narrower beam than the Vipermax. That'll mean the Solent will go faster, but have a much harder ride. It's probably a lighter RIB as well.

I'm hoping my 6.2 Vipermax will top out at 45 knotts with a 150 on. The beam is narrower than the 6.5's so hope it'll be a faster hull.

[Mollers]

[QUOTE=Hightower;218754] They're completely different shapes of Hull, the 6.5m Solent in nearer 7m in length BTW, but has a much narrower beam than the Vipermax. That'll mean the Solent will go faster, but have a much harder ride. It's probably a lighter RIB as well.

If it's nearly 7m and doing 45+knts with a 150 Opti on the back it must be made of tissue paper.

[Hightower]

[QUOTE=Mollers;218794]

Originally Posted by Hightower

They're completely different shapes of Hull, the 6.5m Solent in nearer 7m in length BTW, but has a much narrower beam than the Vipermax. That'll mean the Solent will go faster, but have a much harder ride. It's probably a lighter RIB as well.

If it's nearly 7m and doing 45+knts with a 150 Opti on the back it must be made of tissue paper.

I can't quote on speeds for the Solent, but the hull design is based on a Tohatsu hull I believe. This could be opening a can of worms here

It is quite an efficent design and have been in one at full chat with an HO 200 Etec on the back. Yes, it did hurt

[brucehawsker]

OK. Can confirm that with two blokes (13.5st and 12st) and one quarter of a tank 40 litres with our six pods, anchor, safety kit etc we averaged (I have numbers in front of me) 45.78k according to the GPS on a two way run WOT from approx the Lymington Sailing Platform to Cowes Roads in a light chop (F2/3 - sea condition mild). No it doesn't hurt if you keep a hand on the trim and trim down for the rougher bits. This is with a clean bottom - polished myself (no, the boat, you idjut!) and the engine nice and warm. Temperature about 68c, sunny.

Kev from Solent got it up to 49.1 a while back with the two of us on board with a about a 3 knot current going with us according to the electronic chart - so that is 46k.

I like the noise!!