Volvo D6 DPR drive/HuntonXRS37

[peterunwin]

Hi James,
Subject to weather red Cheetah is about 5 or 6 weeks away from her first test Carbon Cheetah is very much on the back burner as i need Red Cheetah to demonstrate the fly by wire steering system.
Had a very busy weekend, lots more wiring done and also fitted carbon fibre trim rings for the exhausts and cover plates to the rear of the engine vents, she is really beginning to look like a boat again.

Peter

[peterunwin]

Hi All,
The nice weather has enabled me to make lots more progress, finished of all the custom Volvo looms and garmin systems and we were able to switch it on and give it a try, everything configured beautifully so next weekend i should be able to flash the motors up. Also mocked up the cylinders for the carbon fibre trim tabs so we can now mould the re-inforecment all coming together nicely

Peter

[peterunwin]

A few more pictures

[Cookee]

Do they work as a sort of water brake as well? :-)

[peterunwin]

Hi All,
Got the drives installed today, tomorrow i will start the pipe work for the dry sump system.

Peter

[peterunwin]

Hi All,
Fitted carbon fibre air intake for additional ventilation, also filled the drives with oil installed the props and mocked up the transducer brackets.

Peter

[Pennpromo]

Peter,
I think your drives look absolutely stunning, I can't imagine how many hours you have spent just on them ...
I would have liked to see a bit more skeg though ! Simon

[peterunwin]

Originally Posted by Pennpromo

Peter,
I think your drives look absolutely stunning, I can't imagine how many hours you have spent just on them ...
I would have liked to see a bit more skeg though ! Simon

Thanks Simon,
Yes an untold number of hours has gone into the drives way more on the inside….. The skegs have been that size for the last 7 years the only change this time are that they are a little sharper and i have cut the cavitation plates off.These were already fractured above the front prop both sides so would have fallen of anyway.
Today i made all the dry sump hoses between the drives and transom and also did the final fit on the steering transducers these are submersible to 2 meters but should only get splash most of the time.

Peter

[peterunwin]

Hi All,
At last the time has come to get rid of that god awful radar arch it did serve a purpose when we first had the boat but i have always hated it….. I removed the screen a few weeks ago and the replacement is a small carbon fibre wind deflector that now runs full length of the cockpit … much sleeker but it does now mean we have a swimming pool in the cover next time it rains…..

Peter

[Mikko Oikari]

MUCH better!! Like a new boat...

[peterunwin]

Thanks Mikko,
Spent Thursday and Friday trimming the carbon screen also had to cut a 2ft long rebate in the deck as the screen is much longer than the standards one, then yesterday i enlisted the help of my first mate….. to assist with positioning the screen on a generous bead of tiger-seal, a pretty messy job then a massive clean up….

Peter

[peterunwin]

Hi All,
The reinforcement is now bonded to the tab and the final shaping is complete, just need the top weave applying and lacquering then they will be ready for installation.

Peter

[peterunwin]

Hi All,
Cheetah purrs into life both motors started on the button

Peter

https://www.youtube.com/watch?v=MNldI5GadCk

[Ian H]

Thats a big day then Peter. starting first time, You can not be far away from first outing ?

[glen76]

scuse my ignorance, what are the little pipes? and why doesnt water flow get heavier with revs? I was watching swipewipes yesterday, and it was like a tsunami when she was revved.

2 hours leaning on a quay watching boats rev

[Carl]

possibly because it was running on a hose

[Lemz]

Originally Posted by peterunwin

Hi All,
Fitted the raw water pressure relief valves, these are connected with hydraulic quick release couplings which have been machined to reduce their weight, they can also be used for flushing the engines. Permanently fitted the carbon fairlead cover to the nose and also the removable hatch, checked the fitment of the aluminium wing mounting.

Peter

This is definitely one of the most modified installations I have ever seen. Beautiful piece do work. Just one question, why do you need pressure relief valves on the raw water strainers when these are under suction, not pressurised? Isn't this going to allow air into the system?

[NorwegianBoater]

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

[peterunwin]

Originally Posted by glen76

scuse my ignorance, what are the little pipes? and why doesnt water flow get heavier with revs? I was watching swipewipes yesterday, and it was like a tsunami when she was revved.

2 hours leaning on a quay watching boats rev

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

[peterunwin]

Originally Posted by Lemz

This is definitely one of the most modified installations I have ever seen. Beautiful piece do work. Just one question, why do you need pressure relief valves on the raw water strainers when these are under suction, not pressurised? Isn't this going to allow air into the system?

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