MBM Group Test Reduced performance on Sealine SC29

D3B

D3B

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Location
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www.cutting-solutions.co.uk
Have just opened this months MBM and went straight for the 30' Group Test /forums/images/graemlins/cool.gif
Well I would wouldnt I /forums/images/graemlins/laugh.gif

Amazed to find the speed of the SC29 has been reduced from the original figures of 35/37 knots down to 27/29. /forums/images/graemlins/shocked.gif

I was out on Still Dunno (ok she is an S29 not the SC) on Saturday and whilst I could only just get 3700rpm I still manged 34 knots with a bit of tide.

The MBM figures show a vast reduction in speed.
Anyone at SIBS like to question both MBM and Sealine about the reduction?

I would be very intersted to know.

Doug


BTW the SC29 came out tops......again /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif
 
Re: Reduced performance on Sealine SC29

Thats where the article is a little unclear.

In fact closer reading suggests a cock-up in the article

It shows a picture of a single engine installation but the performance info says twin D3-160's (page 47)
Starting price and comparison prices show the same.

Fuel consumption looks a bit iffy too.
my twin's were doing 29 l/hr each at (about....dont remember exact rpm) 3400 rpm and 32 knots with clean legs and bottom. (just had legs antifouled after infestation. didnt bother antifouling hull again as it was in pretty good nick)

Doug
 
Re: Reduced performance on Sealine SC29

It's either a mistake, or it was very rough weather.

I've seen 34kts out of the S28 at the start of the season. Probably down to 32 now with hull slime and half a ton of weed attached to the trim tabs. At least the props stayed reasonably clean.

dv.
 
Re: Reduced performance on Sealine SC29

Just seen your posting, very quick off the mark may I say..
Our SC29 - fitted with twin 160hp D3's - topped out at 29knots in choppy seas and was slightly shy on revs, perhaps due to conditions? This is down on Sealine's quoted 33knots max for the S version. We ran the SC all day and 29knots was the best average figure recorded over a set, 2-way test run. It would interesting to know what installation and model of 29 your figures are based on?

Hope you enjoyed the rest of the test...Carl
 
Re: Reduced performance on Sealine SC29

It's a bit meaningless to quote the "choppy" figures without making that clear: bit like mixing up the wet and dry times on the Top Gear blackboard. Was there nowhere sheltered (ski area etc) you could have used for a proper speed run ?

The Sealine website quotes this for the SC29:

2 x Volvo Diesel D3 160/DP @ 160 hp 36/38 knots

CLICK HERE

dv.
 
Re: Reduced performance on Sealine SC29

Carl

Just changed the header so its not seen as another problem for me....everyone knows I have had problems with the boat.

My boat is S29 hull No 008 (I nearly got 007 /forums/images/graemlins/grin.gif)
Delivered late April 2005
Twin D3-160's
220 hours approx

Just had problem with infestation on drives so she has been out scrubbed down and legs antifouled.
I seemed to be down on power, only getting 3700 max, have normally managed 3900.
On first hard run after delivery I topped 38 knts but that was with tide and speed log needed calibrating.
since then I have regularly achieved in excess of 33 kts....when the engines have behaved themselves! I would be well cheesed off if I only got your sort of performance regularly. i have seen the video clips on the site and would say the sea i had on saturday was similar to that.
Last saturday there was a slight chop down tide and a bit heavier on the return up tide (a forumite might confirm some details). max speed on log showed 34 kts.

Come and give her a trial and report
18 months old /forums/images/graemlins/wink.gif
220 hours /forums/images/graemlins/shocked.gif
lots of problems /forums/images/graemlins/frown.gif

And I am starting to enjoy her /forums/images/graemlins/grin.gif

Doug
 
Re: Reduced performance on Sealine SC29

[ QUOTE ]
This is down on Sealine's quoted 33knots max for the S version.

[/ QUOTE ]

Carl

Must say if those are the figures quoted by Sealine they are well down, as stated by dv on the Sealine site and all previous brochures.

Interesting you say a bit of chop may have caused reduction in top end rpm's

Doug
 
Re: Reduced performance on Sealine SC29

Stupid question. Are your speed figures log or GPS speeds? Its just that you make reference to calibrating your log. MBM's figures will be GPS based for sure but even so, the discrepancy between MBM's figures and Sealine's own figures seems large enough to ask whether there was a problem with MBM's test boat or it was badly fouled
 
Re: Reduced performance on Sealine SC29

Mike
the original speed figures were from last year just after delivery.
Calibration done 17 months ago.

Speed figures are both log and GPS. On Saturday they were just about the same running with the tide that just changed.
Hopefully anothe forumite who was on board will be able to confirm.

Dont the manufacturers usually give them a new boat to test. after all if the boat was badly fouled it wouldnt give a very good result.
 
Re: Reduced performance on Sealine SC29

[ QUOTE ]
Dont the manufacturers usually give them a new boat to test. after all if the boat was badly fouled it wouldnt give a very good result.

[/ QUOTE ]

You would think so, would'nt you? But I read many test reports in the boaty mags in which the test figures are qualified by some statement to the effect that the hull was badly fouled or the props were the wrong pitch or the engines were underperforming, ending with 'the manufacturers reckon they could achieve another x knots if......blah, blah.

Basically boaty PR is nowhere near as slick as, say, the car manufacturers and often test boats are the first off the line with teething probs or a customer's boat which nobody has bothered to check for fouling or performance
 
Re: Reduced performance on Sealine SC29

look at the recent Grands Banks test with the dirty bottom /forums/images/graemlins/smile.gif /forums/images/graemlins/blush.gif
 
Re: Reduced performance on Sealine SC29

Didn't the boat comics complain bitterly about the twin 160 installation and love the single 350? ISTR the twins being very thirsty, or the fuel readings being wrong in the test.
 
Doug tell them what you got in the Humber /forums/images/graemlins/grin.gif

just before we took off /forums/images/graemlins/blush.gif

They will never believe you!

cheers Joe
 
Joseph /forums/images/graemlins/confused.gif

You are not reading everything written in the thread /forums/images/graemlins/shocked.gif

If you look about three posts up I put a 38 kts down, but of course it was tide assisted and the log needed calibrating.

Thanks for pointing out and confirming the speed we did last year.

Doug

Hang on....we punched the tide from Apex /forums/images/graemlins/tongue.gif
didnt we /forums/images/graemlins/confused.gif

Still the log still needed calibrating
 
That,s me told

Why do they call you Mr Grumpy /forums/images/graemlins/wink.gif

cheers Joe
 
Doug

if I was to guess it would be high tide on the button with not a

lot of flow one way or the other .It was definately flat water at

the point of speed trial though(boat would have been very

light at the time)

cheers Joe
 
well it passed so slowly I'm not surprised they got a piccie

cheers Joe

ps tell us how the Moto X went /forums/images/graemlins/grin.gif
 
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