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Old 03-29-2016, 01:35 AM   #48
Baker
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City: League City, Tx
Vessel Name: Floatsome & Jetsome
Vessel Model: Meridian 411
Join Date: Oct 2007
Posts: 7,332
Quote:
Originally Posted by CmdrDick View Post
The turbo isn't getting enough exhaust flow at low rpm to help with the power. That is why many new engines have two turbochargers, one with a wheel for the low rpm range and a second designed for the higher rpm's. Under 1500 rpm, most older turbo engines get little help. A boost gage will give you a better idea about what a turbocharger is doing.
It is called a "sequential turbo" and is not generally found in the boats we are talking about here. It is fairly common in cars. We operate our cars in a wide range of RPMs and power bands. So to avoid turbo lag and then a rush of power, they put the turbos in sequence...to give a more linear throttle response. Boats we generally set the power and are done with it. I guess all I am saying is sequential turbos don't really help in our application. You will see them in very high powered marine diesels....the "MTU range". I am not that familiar with the newest marine diesels so maybe they have small marine diesels with sequential turbos.....
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