Start to Finish: Building Our 50' Skater
#1591
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The first set of engines made their max power around 3200 rpm, and as the rpm climbed they lost a little bit of power but the exhaust temp would climb really fast as the rpm went up to the point that we could not run 3800 rpm because the exhaust temp would be up around 1800 degrees. They are still working on it but With the new setup they are able to turn the engines 4700 rpm at a reasonable exhaust temp and still making 1000 hp. And with cats rpm is king. If we can turn this kind of rpm I may not have to build the overdrive box. We will still have the low rpm torque to get going and then have the rpm range to be able to keep accelerating to a high speed
Last edited by BigSilverCat; 01-20-2018 at 12:37 AM.
#1592
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What kind of hours can you get out of them spinning that kind of RPM? What are your piston speeds at that Rpm? I wonder what I need to do so spin my Yanmars that fast....
65 psi of boost wow!
65 psi of boost wow!
#1594
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Italian guys may find solution to diesel RPM problem. They make very light steel pistons.
https://www.cycleworld.com/2016/01/1...eature#page-26
First piston ring could be higher, so longer rods can be used. This help piston side loads. Another benefit is clearances, they may be very tight, so first ring doesn't get so much violence.
Piston temperature-strenght diagram is intresting. Quite small piston temp rise make aluminium piston double weak than room temp.
https://www.cycleworld.com/2016/01/1...eature#page-26
First piston ring could be higher, so longer rods can be used. This help piston side loads. Another benefit is clearances, they may be very tight, so first ring doesn't get so much violence.
Piston temperature-strenght diagram is intresting. Quite small piston temp rise make aluminium piston double weak than room temp.
#1595
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#1597
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The pump, valvetrain and bottom end are all validated at as little as 10% beyond rated speeds. The % can be that low if you validate on a larger number of the components in question. This reaches the same statistical confidence in the validation. The days of 33% overspeed and overpressure validation is long gone.
all of the accessories could be at risk as well, water pumps, alternators oil pumps etc.
If you’re planning on cruising around the world at 20-30% overspeed you’d be setting yourself up to end up in a bind somewhere.
#1598
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#1599
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Industrial Injection has ran the engine on the Dyno all day everyday for the last two weeks and they have tried 64 different combinations of turbos and they think they have what is going to be a better match for what we need in the boat. Industral has literally thousands of turbos in stock so they could fine tune the setup. In the end we are at 1160 hp at 3200 rpm, 1100 hp at 4000 rpm, and 1000 hp at 4700 rpm. Some of the main differences are the compound turbos which will give us a lot better spool up off the line and then still have the flow for the higher rpm. And the lower exhaust temperatures should make the engine live longer.
They have ordered stainless steel tubing to make new exhaust and intake pipes. I thought they were going to use the black pipes they made for the Dyno but they wanted it to look better and they can keep the setup they are using on the Dyno to keep checking different setups. I'm flying back out there in a couple days to start putting the engine back in and get the boat ready to test once they get all the plumbing done. This time we will probably haul it all the way to Lake Havasu to test. The last time we tested it was not very realistic to what the conditions will be that we are normally running in. The altitude being 6,500 feet changes a lot including lift from the tunnel.
They have ordered stainless steel tubing to make new exhaust and intake pipes. I thought they were going to use the black pipes they made for the Dyno but they wanted it to look better and they can keep the setup they are using on the Dyno to keep checking different setups. I'm flying back out there in a couple days to start putting the engine back in and get the boat ready to test once they get all the plumbing done. This time we will probably haul it all the way to Lake Havasu to test. The last time we tested it was not very realistic to what the conditions will be that we are normally running in. The altitude being 6,500 feet changes a lot including lift from the tunnel.
#1600
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Did Industrial Injection give you any indication as to the Fuel consumption variance running the engines at 3200, 4K and 4700 rpm?
Just wondering if there was any major influence on how the given rpm/ required fuel consumption will effect the long distance capabilities you are after.
Just wondering if there was any major influence on how the given rpm/ required fuel consumption will effect the long distance capabilities you are after.