Turbo vs blower
11-25-2007, 08:09 PM
#21
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Location: Houston, TX, USA
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I had a turbo charged engine in a boat for the last 30 year except for the last 3. My turbo motors with waste gates would go to max boost (I had set for 10lbs) just off idle. The neat thing about turbos with wastegates is I could dial in the amount of boost I wanted, from min. of 5 to max of 15, just by turning a dial on my dash.
My procharged motor will not go to max boost until max rpm.
As to why Mercury not doing it, I think the cost and complexity, and peoples fear of them is why.
My procharged motor will not go to max boost until max rpm.
As to why Mercury not doing it, I think the cost and complexity, and peoples fear of them is why.
11-25-2007, 08:15 PM
#22
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I have 2 friends that bought similar boats back in the early 80's one went the Gale Banks 800HP setup, Other went the roots blower setup. After a few years and a few motors the roots blower guy went Turbos.
11-25-2007, 09:18 PM
#24
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I've always understood that turbochargers are much better for the engine than superchargers.
How much horsepower can you get out of a reliable turbocharged small block marine engine?
How much horsepower can you get out of a reliable turbocharged small block marine engine?
11-25-2007, 09:50 PM
#25
PF Marine
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FACT!!!!!!!!!!!You have to have a load on the engine to make any significant boost on a roots blower.
Rev a roots blower engine slowly up to 5000rpms in neutral and see how much boost you make. Very little, if any.
Now put it in gear and mash the throttle. You'll be very near max boost by 2000rpms and stay there all the way to max rpm.
Rev a roots blower engine slowly up to 5000rpms in neutral and see how much boost you make. Very little, if any.
Now put it in gear and mash the throttle. You'll be very near max boost by 2000rpms and stay there all the way to max rpm.
11-25-2007, 09:58 PM
#27
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23' headed conventional engine around 750 hp reliable
SB2 headed conventional engine around 900 hp reliable
LS1 style engine around 1000 hp reliable
which one do you want?
11-25-2007, 10:15 PM
#28
PF Marine
Platinum Member
The variable vane stuff is cool. The technology (VGT's and modern EFI systems) hasn't really been around until recently, making it now possible to build user friendly turbo aps. The VGT's and EFI systems now available allow for the boost output of the turbo's to be controlled much more easily, making them easier to use at low RPM settings, as well as getting on and off the throttle.
11-25-2007, 10:18 PM
#30
PF Marine
Platinum Member
http://www.youtube.com/watch?v=p4mYHGLAXY0
Nice exhuast by the way. How have they been working? Did you get the pressure pop-off's on your sea strainer?
Nice exhuast by the way. How have they been working? Did you get the pressure pop-off's on your sea strainer?
