Prochargers N Boost..
05-11-2018 | 12:22 AM
#11
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Posts: 75
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From: Arizona
are you running a AWIC?
on a turbocharged engine, yes, this is supercharged. The boost (impeller RPM) is directly related to engine RPM. output increases proportionally to the square of the rotation speed
Let me throw out a couple of thoughts. You are reading the map sensor which reads the absolute KPA the intake is seeing. If the barometer changes, that number changes. You go up to high elevation and the kpa will read a lot lower and your data log would show a lot lower. However if you were looking at a boost gauge it would still read 10 psi boost, which is the amount of pressure above atmospheric you have. So, your data log will read something different every time, but it shouldn't be nearly as much as you are seeing. I also believe that with hotter, less dense air the boost will drop slightly, inlet air temp changes. Another thought, boost is created by load. If the load at a given rpm changes the boost will also change slightly. So weight, trim and water conditions can impact it, especially with a centrifugal as compared to a positive displacement supercharger.
Bob
Bob
05-11-2018 | 07:46 AM
#12
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From: South FL
05-12-2018 | 01:09 PM
#13
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Posts: 3,865
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From: St. Pete Beach, FL
Boost increases fairly linearly with engine speed on a centrifugal I believe.
05-13-2018 | 07:18 PM
#15
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Joined: Nov 2004
Posts: 922
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From: Lago Vista TX
Still trying to figure out why I'm stuck in the 90's, as I have 1000hp and a 290sc hull is supposed to be faster than a 280
Talked with Steve Stepp the other day and it would seem my prop is just too deep.. I'm Saving $$ for a -2 Imco now..
Talked with Steve Stepp the other day and it would seem my prop is just too deep.. I'm Saving $$ for a -2 Imco now..
05-13-2018 | 08:36 PM
#17
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From: Lakewood, NY, USA
Padraig
Last edited by Padraig; 05-13-2018 at 10:26 PM.
05-13-2018 | 09:15 PM
#18
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Joined: Nov 2003
Posts: 825
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From: Antioch, IL
Mine was 4200 lbs dry. I ran a B-max 1.30 with a 28 labbed Bravo. I think I could have run better with a shorty. It was turn key though for 6 years and super quick. There were faster boats at the time they just didn't have near enough lake to catch me. Made 685 TQ at 2800 RPM.
