Volvo D6 DPR drive/HuntonXRS37

[peterunwin]

Originally Posted by NorwegianBoater

Peter I am in awe! What a project.
What effects, if any, do you expect from the cutting of the cavitation plates?

Thanks Norwegian Boater
Both cavitation plates were fractured above the front prop so i figured that it was probably causing quite a lot of drag it also saves about 4kilos per drive in weight, so as the boat gets on the plane really easily i thought it a worth while experiment, i did however keep the parts so i can weld them back on if necessary.

Peter

[glen76]

Originally Posted by peterunwin

Hi Glen,
The two smaller pipes are overflows from the raw water cooling system, there is a cool collar on the exhaust with six 3mm holes drilled into it to allow sufficient water to cool the exhaust the balance overflows via the two small pipes. The cooling system is heavily modified and has the absolute minimum of back pressure as i have found that volume of water is way more important than pressure for good heat exchange. The reason you are not seeing an increase in volume of water when i rev the engines is because i am only feeding them with a 1/2" hose which is no where near enough volume even at idle.

Peter

]

Thanks. appreciate your explanation

[NorwegianBoater]

Originally Posted by peterunwin

Thanks Norwegian Boater
Both cavitation plates were fractured above the front prop so i figured that it was probably causing quite a lot of drag it also saves about 4kilos per drive in weight, so as the boat gets on the plane really easily i thought it a worth while experiment, i did however keep the parts so i can weld them back on if necessary.

Peter

Interesting, cannot wait to see the result!

[Lemz]

Originally Posted by peterunwin

Thanks Lemz,
The raw water system is only under vacuum at low speeds at high speeds the ram effects from the intakes overcomes the volume that the pump can move and becomes a metering unit, when the boat leaves and re-enters the water you can get quite big pressure spikes on re-entry and with the large pipe work i am running to reduce the speed of water, if you don't have a relief valve it could burst the strainers or hose work or even blow the lids of the strainers… i have had this happen on a couple of occasions until i have found a cure.

Peter

Thanks for explanation. How much do you think you have managed to increase the water flow by? I noticed that you have put d6-475 stickers on the covers. Is this currently what you have remapped the engines too? Do you think the engines are capable of >500hp? Or will the cooling system struggle to keep the temp down?

Tim

[peterunwin]

Originally Posted by Lemz

Thanks for explanation. How much do you think you have managed to increase the water flow by? I noticed that you have put d6-475 stickers on the covers. Is this currently what you have remapped the engines too? Do you think the engines are capable of >500hp? Or will the cooling system struggle to keep the temp down?

Tim

Hi Tim,
The water flow increase is significant but i don't want to put figures on it, if you remember the old engines had smaller water pump pulleys this in fact made no difference the reason being that the back pressure through the heat exchanger and charge cooler was sufficient to push the impeller blades of the rotor housing, so regardless of rpm i couldn't get anymore flow through them. On the new system however as well as the pipework being a very large bore with swept elbows the heat exchanger and charge cooler have significantly less pressure drop through them, also the old engines required 40lb of boost to make 400hp, the new 435's only require 29.5lbs of boost for 435hp.I am running them standard at the moment and my guess is with the big exhausts and the improved cooling they will make close to 450hp. As soon as i have established there are no warranty issues i will switch the ECU'S and increase the common rail pressure by 150 bar, at the same time the new ECU'S will give an extra 200rpm, horsepower should rise to circa 500 but i am being pessimistic on my claims on the carbon cam covers.

Peter

[peterunwin]

Hi All,
Cheetah gets her carbon front trim wing permanently installed:huge grin:

Peter

[peterunwin]

Hi All,
Cheetah gets part of her new livery :huge grin: not long now before she gets wet..

Peter

[hunton69]

Sorry to say but that wing looks awfull

Fare play to try new things but I can't understand what it's going to achieve.

[Ian H]

like the graphics. If you do not mind asking where did you get them from ?

Looking forward to seeing you out on the water

[peterunwin]

Originally Posted by hunton69

Sorry to say but that wing looks awfull

Fare play to try new things but I can't understand what it's going to achieve.

If we were all blessed with the same sense of adventure we would still be riding round in coracles.

[peterunwin]

Originally Posted by Ian H

like the graphics. If you do not mind asking where did you get them from ?

Looking forward to seeing you out on the water

Thanks Ian,
The graphics are a tweaked version of the ones we developed with Dan from Premier Vehicle Wrapping for Carbon Cheetah, we got the name on today

Peter

[glen76]

love the graphics. Have I missed pics of upholstery?

[peterunwin]

Originally Posted by glen76

love the graphics. Have I missed pics of upholstery?

Thanks Glen, in my rush to get the boat ready for the graphics i forgot to take any pictures of the upholstery, will get some next weekend as i have been rained of today.

Peter

[peterunwin]

Hi All,
Fitted Cheetah's seats and side panels also fabricated a stainless steel bracket to hold the steering joy stick so i can now use the steering wheel or the joy stick for steering. We also finished of the starboard side graphics.

Peter

[Carl]

beautiful work,but that wing isnt for me

[Mark Wildey]

If Scotland split from the UK, you'll have to get rid of the blue

Looks great by the way

[Jizm]

Looking really good Pete.....

[pugracer285]

Originally Posted by peterunwin

Hi All,
Fitted Cheetah's seats and side panels also fabricated a stainless steel bracket to hold the steering joy stick so i can now use the steering wheel or the joy stick for steering. We also finished of the starboard side graphics.

Peter

Lovely work but the fuel tank looks a bit small

[Captain Chaos]

Originally Posted by pugracer285

Lovely work but the fuel tank looks a bit small

No Silly, its fly by wire fuelling

[Bob Webb]

Originally Posted by peterunwin

Hi All,
Cheetah gets her carbon front trim wing permanently installed:huge grin:

Peter

Peter, I do wonder if painting or coating the bow-wing support Team Unwin Red would make it appear far more integral to the boat structure, rather than a mechanical add-on.
Also perhaps a subtle red stripe or two along the outer wing endplates would reflect the general bow lines and paintwork.

Do like your joystick steering override arrangement. Very tidy and practical.