Actual hp?

[swof63]

Yes the Zuk I4 200 weighs 240kg so not quite the lardass.

Being all about torque, interesting to note the zuk 115 makes 164nm @4500 rpm ( the zuk 140 makes 165 @ 4500 rpm ), the merc 115 makes 162nm @ 3500 rpm.
The merc 150 makes 244nm @ 3000 rpm ( the zuk 200 makes 249nm @ 4000 rpm ).
The old Yamaha 2.6 lt 150 makes 228nm @4000 rpm, the new yam 2.8 lt dec 150 makes 242nm @ 4000 rpm.
This makes everything clear.


Sent from my iPad using Ausfish forums

[ranmar850]

Bit unfair to quote the 6 cylinder weights for the Zuk and the one way bars you have up your way sound interesting . We will have to agree to disagree on the holeshot - the bars over here we have to go out first to get in and holeshot can very much be an advantage. I do agree with the final statement - with all other factors being fairly equal, torque does indeed rule.

But going out, unless you want to be playing wave jumping hero, you are not after speed? You need to be able to move to the next one, touch of throttle to lift the bow as you hit it, throttle back? Then when it is looking clear of breakers, go as hard as you want? I guess they are all different to some extent--if you can see a lull, go for it, some don't really seem to lend themselves to that approach? ie, Noosa, slow and steady seems to be the approach/?

[scottar]

But going out, unless you want to be playing wave jumping hero, you are not after speed? You need to be able to move to the next one, touch of throttle to lift the bow as you hit it, throttle back? Then when it is looking clear of breakers, go as hard as you want? I guess they are all different to some extent--if you can see a lull, go for it, some don't really seem to lend themselves to that approach? ie, Noosa, slow and steady seems to be the approach/?

No wave jumping hero here - quite the opposite but on more than one occasion I've made it over breaking waves by the skin of my teeth and on plenty of occasions not. I know which of the two conclusions I prefer. Both Jumpinpin and South Passage bars can be quite lengthy transits with multiple banks at times depending on conditions. The crossing process usually involves attempting to avoid breaking waves altogether or at times depending on the bank configuration, skirting around them as they appear. Either way you can be going from semi displacement as you crest a swell (to avoid the wave jumping hero activities) to plenty of revs to either get to and over the next one before it breaks or skirt around it if the option is viable. A reduction of a couple of seconds in holeshot can make all the difference in the world as once your in, there is no turning around some days. It was quite interesting when I first moved to Perth looking at the power plants fitted to a lot of the 6 plus metre rigs and thinking they were "small" by comparison to what I was used too in Brisbane courtesy of a minimum requirement for bar work.

[Crocodile]

Hello johnjvv,

There is a USA website
https://www.epa.gov/compliance-and-f...-and-equipment

Have a look at their test spreadsheet and you will see substantial differences in rated V actual HP.
One of the columns is in Kw to convert Kw to Hp X 1.34.

I have read somewhere that the 10% rule applies.
Individual machines can differ as well. Have you ever worked somewhere with a fleet of identical cars and one goes much better than the others?
Makers also have high performance models. ETEC in the states has HO models and the 90 HO is suspiciously like a re-badged 115.
ie. a stock 90 is three cylinders a HO 90 has four cylinders.

I think that it is high time outboard manufacturers published Hp, Torque and fuel flow charts as most diesel engines have.
I anybody knows where to find such charts please share.

If you study the published bulletins from the various makers there is very little difference between them.
A good rule of thumb is that a carb 2 stroke produces 10Hp for every gallon per hour.
Injection 2 stroke and 4 stroke about 12Hp.

[ranmar850]

Some would say this is the worst "bar" on the West Coast, this is where I live

On a very calm day




With some swell it changes, a lot





You are really only going through white water, but it is known as "the washing machine" for good reason. People come to grief every year. I personally reckon that Horrocks Beach, just down the coast from us, ( The second-best beach in Australia ) is the worst--you are running straight into the swell across a reef bar, and I punched a window out in a 38 footer there once.
But we don;t have those river bars. I grew up over there, have been through a few--Narooma, Swansea--you can have 'em.

[scottar]

Looks like a good access on that northern side with a quick squirt to get across the face of the rocks. Does it ever close out?

[ranmar850]

Yes the channel is on the right, you can't see the reef in the shot with the swell in it. it's pretty straightforward, really, in average swell conditions, blokes hammer out there in 12 foot dinghies. It often doesn't look to bad to the inexperienced eye in a swell, but, then you see a boat going through and realise just how big that messed up slop is, going all directions, backwash off the reef, waves breaking unpredictably across the whole . It does close right out on a big one, but you shouldn't be out there in a trailer boat long before it gets to that stage. Worst I've seen it personally , you were waiting a full 3/4 mile NW from the little rock you can see sticking out. The whole bay was closing out, huge. I sat out there on the flybridge of the relatively fast 50 footer I had at the time ( 24/19 knots), had three false starts and had to retreat before I could make it in. Luckily don't get them that big every year. But it was even bigger when Cyclone Alby caught everyone out at sea, awesome video floating around of that day.

[Noelm]

Speed is not everything when crossing a bar, it's nice to have, but can certainly land a novice in trouble, anyone who has done a lot of surfing will be able to recognise how a wave breaks, taking it easy can often be the best option, but, having a bit of speed on hand can be of benefit, lots of 9knot trawlers cross bars everyday, and certainly do not have the luxury of speed or hole shot!

[scottar]

No it may not be necessary but it's a tool you can't use if you don't have it. Then you have to substitute bulk,drive characteristics and design. I dare say if most trailerboats only did nine knots they would look markedly different or there would be nowhere near as many crossing bars. I've driven the Gold Coast Seaway on a big swell in a displacement vessel. Prick of an idea if you ask me.

[johnjvv]

Hello johnjvv,

There is a USA website
https://www.epa.gov/compliance-and-f...-and-equipment

Thats great thanks Croc!

[inveratta]

Another engaging thread to read......At an older age ..I offer the following....when you talk to a sales rep and he/she start bagging the opposition..tune out..thats not the person you want to talk to....I usually politely say something like..thats interesting and tell me ..whats the worst thing about your motor or whatever? Normally followed by an awkward pause.

Some of the comments about how you intend to use the boat matters............. reflect a lot of sea hours..

For myself...when I repowered I walked in thinking ABC and purchased CBA on advice..couldnt be happier.

lol but then again its a merc150!!!

[ranmar850]

They are all good, nowadays, really...just pick your particular poison and choice of cowling colour.

[ranmar850]

Makers also have high performance models. ETEC in the states has HO models and the 90 HO is suspiciously like a re-badged 115.
ie. a stock 90 is three cylinders a HO 90 has four cylinders.

You only need to look at the the actual engine capacity of each HP output and you will see that they often share the same bore/stroke over a number of models. The HO Evinrudes suffer, IMO, in that the lower HP models using the bigger block suffer a real weight penalty, both G1 and G2's. The torque from the larger displacement block will be an advantage, but the ones I've considered were just too damn heavy for their HP, torque or not. 244 kg for the shortest shaft, and expensive to boot. same displacement as the 300HP.

[ericcs]

i know it's irrelevant now, but back in the old days, HP was measured either at the flywheel, or at the prop, depending on brands. I found it just as confusing back then!

[scottar]

Biggest issue weight wise with the G2 is the inbuilt power steering. Compared to similar Mercury products with the power steering added I don't think the difference is as extreme. Torque - the big block has it in spades. The G2 200HO compared to my G1 is a grunt machine - same top end but totally different through the rev range and massively better ( like almost double ) fuel economy on the same hull but yes - they are heavy in comparison to the new V6 stuff from Mercury (keen for a look at these) but not the V6 products from elsewhere. I have mates that have recently repowered Victory's - one with the small block 200 without the steering (special order as they don't usually carry it apparently and only weighs 225Kg) and one with the 200HO - similar top ends, the small block is the better of the two on fuel and performs better than the G1 250 it replaced in all aspects apart from top end including holeshot from the owners perspective. I am looking forward to water time with both to see the difference first hand. The new Merc V6 is hard to pass up though - they have really raised the bar with their latest generation in the weight stakes.