Hunton/ilmor Build

Hi Peter thanks for your reply probably like a lot of people on here I recalled your upgrades on the Hunton diesel engine and you really started to get some great performance from that pleasure boat, I must admit I somehow doubted it was the same boat as you mentioned stretched XRS37 making it 39'6''
I bet you are are on great terms with Hunton that's some serious investment in their product you have, out of interest does this mean your new creation has the identical hull to that of Kent koi which has been redone by Hunton and will hopefully come out next season to challenge the field which I seem to recall reading now has petrol engines too

I am not an engineer but realised from a young age that up-scaling CU inch's does not translate to a similar up-scale of HP in most circumstances as can be noted many car manufactures have boasted easily getting as much as 230-240hp from their 2ltr diesel engines but longevity that may be something else, but when you increase their CU inch to 10-12ltr the efficiency numbers start to decline to the point 100hp/ltr is really an outright racer of very short engine hours between rebuilds and much the same goes for petrol too
 
More pictures of Hunton/Ilmor

More pictures of Hunton/Ilmor
 

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Lot's of 'Yellow'! nice.

So the longits were obscured from view by the companionway.
 
Lot's of 'Yellow'! nice.

So the longits were obscured from view by the companionway.


Hi Jon,

Jeff Hunton will post later with some of the more intricate build details. The boat as pictured inc. 1200ltr fuel tank weighs in at 2.1 tonnes

Peter
 
I just don`t believe it!

Hi Peter,

A few more numbers for you to play with.

37ft alloy OPI - 2 X 1200HP Petrols - 8ft beam

As calculated (kg)

Alloy hull - 1400
Hull & S/S Ftgs - 63
Deck Eqip -49
Systems - 190
Mchy - 1394
Seatings - 46
Electrics - 127
Nav - 21
Accom - 24
Flats - 19
Paint -5

TOTAL -3338KG

F.O. (Full) - 1140
Crew -271

TOTAL -4749KG (a CUV38 should be circa 5t)

40ft GRP (ABO) - 1240KG grp hull wt inc tanks (alloy boat equiv was 1400kg for 37ft)

So the show stopper is 2100 kg for an equivalent Hunton? Nah,something wrong here. There would be nearly another 2t of fitout plus over a ton of fuel which would make the boat 5.1tons full. Back to the drawing board!
 
Can somebody please confirm that the Marathon weight rules.... is it after the race with what fuel remains, is the weight of the crew included?... or is the boat weighed before the race & includes full fuel/crew
 
Post race, with residual fuel. not including crew.
 
On a more serious note what do you mean by "crane wts can be a bit iffy" !!!!!!! explain yourself Mr Fishy :hugegrin:
 
Dodgy old cranes? dodgy old crane drivers? :hugegrin: :seaman:
 
Mmmm i must remember that comment next time im at drivers and about to lift your boat :hugegrin:
 
Crane Wts

The `iffy` crane wts are based on past experience when compared to load cells shortly afterwards,but of course a man of your ilke would have cranes that would feedback data cock on ,and anyway why aren`t you out in key west showing them yanks how to `dump` a boat in.
 
Peters boat is mostly Kevlar, some carbon and all panels are sandwich construction. Balsa in bottom, high density foam elsewhere. All the bulkheads and longitudinals are composite, no wood.
The hull mould has been modified from the original that Kent Koi/Garmin came from, Peters incorporates a pad. We also have tooling to produce a stepped hull version and this will be offerd next year as an option on our XRS 37 model.
The highest speed we recorded in Kent Koi before handing over to Chris Scrag and Glyn Evans was 78.2 knots.( 90 mph ), with 2 x 600 Sabres, Arnesons and light fuel load. Two way average on measured mile in Southampton water. Didn't have GPS in those days!
I reckon Peter will be good for 88+ knots.
 
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Just throwing some things around here on the statistics front for a bit of fun and going on 3.7 ton's (around 3800kgish)and 1450hp, a P1 multi stepped Evo boat would weigh in at 5075kg with similar power but set up as race only would know doubt have to top out over 120mph to be in the shout some 20ish mph faster

the boats in OSS Vee in the USA are around 40' and did have a minimum weight of around 3700KG so assume the boats came in rigged under that weight and with a canopy running 2x525hp although with blueprinting maybe 560ishhp and ran up around 112mph in a flat water race now they have adopted the P1 rules inc speed limit's :aaahhh: so they are a similar weight set up as an outright racer with a stepped hull but 350hp less but still 10mph quicker

A class 1 monohull back in the day I think had a min weight of 4500kg so flyingfish's 4700kg seems to fit in with this and around 1450hp was all out then so again more weight for the same power however in this instance the class 1 would probably be slower with the extra weight carried, so low to mid 90mph about it

which leaves the new super machine with the power/weight of a modern class 1 cat either being weighted down or running in basics like the Brass monkey un-weighted ... yes please Peter just go for it :up:
 
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Hi Peter,

A few more numbers for you to play with.

37ft alloy OPI - 2 X 1200HP Petrols - 8ft beam

As calculated (kg)

Alloy hull - 1400
Hull & S/S Ftgs - 63
Deck Eqip -49
Systems - 190
Mchy - 1394
Seatings - 46
Electrics - 127
Nav - 21
Accom - 24
Flats - 19
Paint -5

TOTAL -3338KG

F.O. (Full) - 1140
Crew -271

TOTAL -4749KG (a CUV38 should be circa 5t)

40ft GRP (ABO) - 1240KG grp hull wt inc tanks (alloy boat equiv was 1400kg for 37ft)

So the show stopper is 2100 kg for an equivalent Hunton? Nah,something wrong here. There would be nearly another 2t of fitout plus over a ton of fuel which would make the boat 5.1tons full. Back to the drawing board!

I JUST DIDN'T BELIEVE IT EITHER!!
Hi flying fish, thanks for clearing up the weight issues i have always thought Cinzano to be lighter than originally quoted to achieve the performance levels it does i.e. much better power to weight ratio than my original calculations.
Hunton Illmor The 2100 kg does include all deck fittings,engine hatches, exhaust tail pipes & engine mountings. The mooring cleats have been specially reinforced & double as lifting eyes. The Illmor engine, drives, gearbox & headers including all fluids only weigh 1120 kg so based on my calculations the boat will weigh 3700 kg with 100 litres of fuel on board, 4484 kg with a full fuel load but the load cell never lies & i will be honest with my findings when she is finished.
Part of Jeff's brief was to build a hull as well as being reasonably light also to be incredibly strong.As all year round boaters we do occasionally get caught out in some really shitty weather & i want to be able to drive it really hard, bearing in mind it is a production cruiser based design you could liken it to the clapped out old banger sitting next to the 911 at the traffic lights little does the 911 driver know there is a Blown Big Block in the back of the banger.
Peter
 
I think weight is becoming to much of an issue unless the boat is full of steps.
Set up will be more important for total outright speed.

Good marathon boat needs lenght no steps lots of GGs and a throttle man with big balls
 
Latest weights

Thanks Peter for coming back with the weight picture.The clouds have parted and can now see the overall picture,so it looks like there are some big savings on the construction weight which is no mean feat.

I think a comment may be needed for `Hunton 69` re wt becoming an issue.
No sir,not at all.When wts are given out that indicate a super lightweight hull,it creates interest to see how it was achieved.The wts given out more often that not never really state exactly what they represent,and that`s what leads to the dialogue to find out.

Forget the Marathon tag,that`s only good for RB08 races,and most boats in that aren`t especially built overspec from a CTC type race,if anything for a single leg in RB race a boat is less stressed with max power not being used.It`s the overall fatigue level that is difficult to judge,which is probably why a boat like Swipewipes was built slightly heavier than normal.

Wt is important along with all the other factors, steps and all Mr.Buzzi.It`s the combined package that is the trick to decide what sort of races you are likely to be successful in.There is no such thing as the perfect boat for all race circumstances.
 
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Hi Peter,
I must admit a 38ft boat with 1450hp and with that sort of lightweight in race conditions seems getting on the hairy side,considering they reckon a CUV38 travelling over 90mph is becoming a bit unstable,even lightweight U.S. monos are a bit longer to handle that sort of power.There was the CUV 38 San Benedetto which had 1640hp,but that was regarded as on the limit.

Flyingfish when you say the the CUV can start to get a bit lively beyond 90mph is that only the 38' and not the 41' boats as Follett cars being the stretched version at 41' seemed to be pretty stable in the mid 90mph region ( I recall JF saying Richard Carr was thinking of perhaps bringing this back on some thread:up: ) plus it also had as you say on the limit 1600+hp from it's deisel engines
And then their is perhaps the fastest ever CUV Thuraya with it's 850+hp lambo's weighted down it probably still reached around 100mph although not competitive against it's newer arrivals in the speed department but what would it have done without the weight penalty
 
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Hairy CUV 38`s

That was a comment made after San Benedetto swapped ends in the CTC 87,that over 90 mph a CUV 38 began to get a bit uncontrollable.
No feedback on the CUV 41.
I dare say if one looked hard enough you could find a 38ft with more than 1640hp.
Is the Hunton a 38ft,a 37ft or a 39ft ignoring the model No.It sounds it maybe a 39ft with slightly more beam than a CUV38,and hence the lighter weight for that size of boat.
Incidentally SDA (cuv41) with 1600hp,averaged 85,5mph in a light condition race.
 
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