One for speedboats techies

Nope, that friend of mine had the opportunity to try a very fast boat in the meantime and has now been bitten by the speed bug...
...hence the reason for this thread!
Though his missus definitely prefers the Cobalt, so who knows?
I won't forget to post my impressions, if and when he would decide to make an offer and eventually test her.
Thanks for all your suggestions so far, anyhow!
 
[ QUOTE ]
you got me, I now believe your 9g claim

[/ QUOTE ]Hey, you tried to get me and my honest claim, in the first place! /forums/images/graemlins/smile.gif

Re. the radar, I'm sure you won't miss anything with the 4kw digital.
But weren't you comparing the 4kw digi with the 12kw digi at that time?
And as I recall, the price difference you mentioned was much lower - a few hundreds quids maybe?
I'm sure I supported the bigger one, and I don't think I would have, with a grand of price difference and for "just" the analogue...
 
Yes you're right, the comparison was 4 vs 12, not 10.

I thought it was about £500 price difference, but I was wrong (mix up between price of digital and super digital - Raymarine confusingly do 2 digi products) and it turned out to be something like £800, though I dont remeber precisely. Anyway, the day I talked to (helpful) Raymarine and they told me 4kw digi was almost as good as 12kw digi, and both were much better than analogue, I think I was feeling tight (financially) so I placed the order for the 4kw super digital! Something like that anyway

No regrets anyway. The 4kw digi seems superb, at least in the few hours I have used it...
 
Aha. Weird, I'm having a quick look at their website and apparently they have a choice of two 4kw open arrays, a 48" and a 72"... /forums/images/graemlins/confused.gif

PS: wait, apparently the 72" has a 72nm range, and the 48" - guess what - a 48nm range. But they're both 4kw. Funny combination!
 
Yeah, I was suspecting the same.
Good for them (and their customers) that their engineers are better than their webmaster! /forums/images/graemlins/blush.gif
 
We have 2 of the 700sci's in our Nortech 36 and they have been very reliable, but I always give them a very thorough preflight before we take the boat out, you don't want one to stop suddenly when you are doing 120 kts in a cat! These are the biggest engines Mercruiser do with a warranty. The only real problems have been with the props throwing blades at $7000 a pair , the last nearly cut through the cavition plate.
We have 2x 1250 hp engines on their way over fom the states now to go in our other Nortech 36, can't wait to test those which should be good for 140kts+/forums/images/graemlins/grin.gif
Its amazing how much the air in the tunnel contibutes, with the drives trimmed in at full throttle it does about 85 kts, just trimming out raises the speed to 120+ as the angle of attack goes positive and air starts to compress under the deck between the hulls, you definitely feel her starting to fly and get light on her feet, and its like you suddenly found another 30% throttle. Also the rpms spin up as the surface props are unloaded as they break the surface, its amazing the speed can be increased so much with a just a press on the trim button.
I used to think 40kts was fast but now 80 is the point where it starts getting interesting, you have to be a mile ahead of the boat as you can't turn fast at those speeds, its a bit like doing 120 on the motorway and everyone else is doing 40 or less, you soon can find yourself running out of water if the fjord isn't very wide.
 
Interesting stuff, thanks.
By very reliable, do you also mean in terms of durability?
I mean, how many hours is an engine like that supposed to last before needing a rebuild?
Assuming it's properly used and maintained, of course (and not used for racing).

Re.props, wow! Are you sure you didn't hit anything?
At that price, I'd expect them to do their job without throwing blades around!
Not a big problem for the kind of boats my friend is looking at, though: 26' or so monohulls, good for 70/75 kts max.
Surely not too shabby (particularly when you think of pulling a skier at that speed /forums/images/graemlins/shocked.gif), but in a totally different league if compared to a Nortech, anyway....
 
We use ours for speed trips, folks who want to join the 100kt club and get a certificate to prove it, team building, stag party present etc.
Also its the pace boat in our Poker Runs, so its been up to Bergen (100miles) a few times and down to Arendal (150 miles) and she runs fine, obviuosly we only go full throttle part of the time as the fuel consumption is then up at 300 ltrs p.h.!
The engines had a few minor leaks but that was production faults, otherwise they run fine and have given no trouble. The exhausts have to be removed once a year and pressure tested, two of ours had leaks one external so we spotted it, the other internal but luckily it was at the collector so the sea water went out and not into the motor. They are expensive to replace if they can't be welded, about £10,000 a pair norwegian prices, but cheaper direct from the states.
think of it as owning a Ferrari, you don't skimp on maintainance, and a lot of the servicing is preventative maintainance, looking for problems before they get too big or potentially dangerous in view of the speeds.
 
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