cosworth rib - Page 2

Pash 1 · 13-06-2009, 06:24 AM

Bling Wheels on that trailer

cosworth mirage · 13-06-2009, 11:52 AM

Quote:

Originally Posted by Pash 1

Bling Wheels on that trailer

cosworth mirage · 15-06-2009, 06:14 PM

Hoping they will distract eyes away from the slightly rough looking rib going on it.

cosworth mirage · 30-04-2010, 06:24 PM

done some mods over the winter moved the engine gauges into rear of cockpit and gps into the front ,was having a bit of trouble keeping a close eye on the gauges and the water at the same time.
trailers all finished and rebuilt the upper gearbox.
trim tabs on .
we have been out testing a couple of weekends know and its starting to feel like its getting something like it.
first test was 4000rpm for 15 mins just to run everthing in and then a good check over for leaks etc
then ran upto 5000rpm 40mph exh temp 905 coolant 70 boost 5.5psi
the boost was to low for the water inj to cut so made a couple of adj
6000rpm 50 mph exh temp 890 coolant 70 boost 6.5 psi

throttle is about 60-70% boost is hardly coming in with the light loading on motor

going to run it at 6500 and 7000rpm this weekend and see how that goes
been testing with full fuel load 300ltr .its going to need a bit more pitch to get the best out of it but i am trying to take the speed up gradually and not melt anything if i can help it.
the engine is setup for 350 bhp at 23 psi boost i think its using about 170hp to so far i will have to keep a eye on the exh temps to see how much boost it can run with the present engine setup.

p.s will post some pics next week

cosworth mirage · 30-04-2010, 07:45 PM

photos

baj666 · 01-05-2010, 05:49 PM

Quote:

Originally Posted by cosworth mirage

photos

love the exhaust, reminds me of a turbine exit

larby · 01-05-2010, 08:28 PM

Love the boat in general!! This thread has always really interested me!

It's looking really good, but would benefit from losing the a bar in my opinion! Couple of questions...
What drive are you using, and whats the reason for using it as opposed to a bravo?
Why go for a cossie motor opposed to a super/turbocharged marine motor?

Great to see someone doing something different!

James

cosworth mirage · 03-05-2010, 10:51 PM

Thanks for your input
Done a lot of work with these cosworth engines in the past and know they can make good power.I thought the v8/bravo setup is a bit to heavy for this size boat and didnt fancy having a big outboard engine again. Getting the boat working and reliable upto 35-40 knots was fairly straight forward but getting to my target of 60-70 is not proving to be as easy. Without any previous inboard boat engine experience i set the drive to low and added more and more power to try and increase the speed but ended up just blowing the first drive leg (volvo 200) then tried the larger 270 drive that was worse,then saw a boat with a 270e drive on which is a straight swap brought the boat switched drives and sold it on. The e drive is a twin pinnion drive like the mercruiser speedmaster drive and much shorter which is going some way to correcting the drive height issue and seems to have made a big change in the whole boat dynamics. Ran the boat sunday a had it up to 7000rpm in 2-3 ft messy chop and was running well but really needs more pitch now to make any more gains.
Fitted another water injection nozzle just before the turbo intake hoping it would cool the compressor and then condense in the intercooler and then go onto its usual job of cooling the combustion chambers and its knocked 100c of the exhaust temp at 6000-7000rpm, So i should be able to wind in some more boost with a new prop and make some gains..

maybe

cosworth mirage · 06-05-2010, 02:08 PM

Some pictures of outboard steering system adapted to fit
electrical side of engine with seawater pump for chargecooler-first stage engine heatexchanger and turbo/exhaust cooling. Second stage heatexchanger is scoop feed from hull. Exhaust is dry with thin water jacket around muffler. Hot side of turbo and manifold are isolated from the rest of the engine bay but vented through air feed and vented side panel.

cosworth mirage · 15-05-2010, 10:20 PM

The volvo e drive leg has no water pick so i connected the intake to the sea water filter to the scoop feed of the secondary heat exchanger thinking this was the best solution, it was until you go over 50 mph then the cap blew of the seawater filter chucking water everywhere.
Refited cap and crawled back to port fitted a restricter in the filter line and a return pipe from the top of the sea water filter to the transom and pointed it at the top of the drive leg for a bit of free cooling with a check valve to stop air getting in at low speed.
Got to 50 mph and the cap blows again, checking the pressure on the return line its not much over 2-3psi but it seems enough to blow the cap.
I,m thinking of either removing the filter and risking some weed intake or replacing the filter with something that will take the pressure or finding a way of getting a unpressurised feed from another place (front of the drive leg would have been good)
Got another prop on the way with more pitch so will try and solve the water issue and then retry next week.

cosworth mirage · 26-07-2010, 09:30 PM

Have had a suspicion that the previous raw water cooling problems might have caused a problem with the engine as it started blowing a bit of coolant out the header tank when boosting over 12psi, so friday carried out a pressure test on the cooling system and discovered the cap was venting out coolant at 10psi and not 20 due to slight pitting on cap seating, so lapped the seat nice and smooth and rechecked and it was now holding 20psi, I left the pressure gauge on the cooling system so we could keep an eye on things when out on the water.
launched that eve about 7.30 and ran 3-4 miles before winding in some boost and the pressure started climing right upto 20psi and then vented so had to slow down and let things settle a little ,feeling rahther pi##ed off i ignore the advise of my co-pilot and thrashed the s##t out of it back to falmouth with water blasting out the overflow and launching off the pilot boat,s wake at about 40kn,s .
got back ok and felt a little better

got the boat back to the workshop and set about stripping the motor,saturday evening fitted new gasket and got it all back together,I was starting to doubt weather it was really going to fullfil my aspiration,s, so set a plan for sunday afternoon testing.

The plan was to push the engine further than ever before and to hell with the consequence .so sunday afternoon left falmouth after some pre-checks down to the pandorra inn, cooling system pressure at 10psi engine 80c ,all looks good quick pint and rechecked the levels all ok. Left the pan got her up onto the plane and wound the boost upto 1 bar and nailed it and held it there for 10 minutes without any problems we ran at 53kn on gps and no problems egt 875 coolant 90 rpm 6000 ,stopped for a couple of minutes to catch our breath and nailed it some more,and more.

took her back and and everthing looks good I have had a good check over and dropped the drive oil and lower g/box cover and I,ve still even got a full set of teeth, there is still another 8psi of boost in the engine setup and 75-100c of egt in the bank to get to 7000rpm but not sure about pushing much harder intill later in the season as it might be nice to actually get some time on the water for some fun

I am really relived to find that,s its not a complete dud after all the work i have put in its never going to be a really reliable boat but not many fast boats are but its starting to tick all the right boxes for me

cosworth mirage · 27-07-2010, 11:32 AM

Prop is now 13x19 3blade cleaver with 1.51:1 ratio box.

cosworth mirage · 20-01-2011, 10:21 AM

Started to pull the motor from the rib last week, the couple of overheats the engine sufferd last year during testing took there toll on the engine compresion and made it a bit laggy on boosting up, then lots of engine breathing and oil leaks on boost .I have started building up the replacement engine which is the later and stronger 4x4 block and will fit it with low comp pistons to allow more boost.
Looking at extending the sump and pickup to increase capacity and fit a stainless coil in it to allow the raw water to cool the oil better and changing the water injection setup to port injection with 50/50 methanol so i can add some more ignition advance, may also look at ceramic coating the pistons and combustion chambers if falls within budget. On the intake side of things there is now a secondary massive charge cooler to mount on top of the engine plus some mods to the inlet manifold to give more plenum volume to carry out .
During the last few testing sessions i fitted a innovate air fuel meter and data logging display unit this shows the rpm/afm/inj duration/and temp,s ,with variable resister fitted in line on the engine coolant temp cercuit I was able to alter the engine fuel mix to trim the fuelling against the rpm and exh temp to max out everything .

The quest for more power continues Gary

Cookee · 20-01-2011, 12:08 PM

Quote:

Originally Posted by cosworth mirage

Started to pull the motor from the rib last week, the couple of overheats the engine sufferd last year during testing took there toll on the engine compresion and made it a bit laggy on boosting up, then lots of engine breathing and oil leaks on boost .I have started building up the replacement engine which is the later and stronger 4x4 block and will fit it with low comp pistons to allow more boost.
Looking at extending the sump and pickup to increase capacity and fit a stainless coil in it to allow the raw water to cool the oil better and changing the water injection setup to port injection with 50/50 methanol so i can add some more ignition advance, may also look at ceramic coating the pistons and combustion chambers if falls within budget. On the intake side of things there is now a secondary massive charge cooler to mount on top of the engine plus some mods to the inlet manifold to give more plenum volume to carry out .
During the last few testing sessions i fitted a innovate air fuel meter and data logging display unit this shows the rpm/afm/inj duration/and temp,s ,with variable resister fitted in line on the engine coolant temp cercuit I was able to alter the engine fuel mix to trim the fuelling against the rpm and exh temp to max out everything .

The quest for more power continues Gary

Wow!

baj666 · 20-01-2011, 07:40 PM

bloodyhell you could'nt of picked a more awkward motor to keep cool and happy at high psi...had a cossie once and it was a nightmare in a car so it must be a massive task to maranise <<<<(spell) one..well done

midnight club · 20-01-2011, 07:42 PM

Quote:

Originally Posted by Cookee

Wow!

YOU WILL NEVER HAVE ENOUGH POWER LOL

cosworth mirage · 21-01-2011, 08:17 AM

Quote:

Originally Posted by baj666

bloodyhell you could'nt of picked a more awkward motor to keep cool and happy at high psi...had a cossie once and it was a nightmare in a car so it must be a massive task to maranise <<<<(spell) one..well done

Yep i think if you were looking for a petrol powered megawatt water heater then this is the tool