Comments by "Lifted_Above" (@lifted_above) on "Does a Rear Mount Turbo have a Lot of Lag? Remote Mount Turbo Benefits and Drawbacks Explained" video.

Aren't you guys just trying to speak about the containment volume of a cylinder? Which is nothing but the area of a circle, times length? Gas flow is a lot like water flow, just much less dense. You have both a volume of water and a velocity. You have both a volume of gasses and a velocity. Diameter of the plumbing affects volume and velocity, one way or another.
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It can get very complicated very quickly, when you consider material types, thermal conductivity of those materials, surface condition of those materials, the differential of temperature between the inside and the outside, and how tightly the bends are in that tubing where there are corners. So much of it is kept simplistic and generalized because the minutia isn't worth considering.
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One could have a thimble with 40 psi gas pressure inside it. Internal volume is extremely low. One could also have a 55 gallon drum with 40 psi gas pressure inside it. Internal volume is monumentally higher than the thimble. The amount of time it would take to relieve/equalize those internal pressures to the atmosphere is drastically different. Thimble would be an instant fizz. The drum would be a large blast and take much longer. The potential energy between these two vessels pressurized the exact same internal pressure is also drastically different. Going further, assuming air/fuel ratio to be the same between the thimble and the drum, far more energy is available in the drum, even though pressure is exactly the same.
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Yes there's a problem: The lawmakers.
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So much of getting a subject across properly these days, is battling the misconceptions or misapplications of WORDS to what is being meant. Contemporary use of a specific phrase or word is often entirely wrong. Getting over that is hard. Thanks for the work you put into this.
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Potentially. There's the issue of turbo shaft seals allowing combustion gasses to pass through, depending on the condition of everything.
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@Phantom-mk4kp If a turbo is generating at least 30 psi pressure on one side, and exhaust gas pressure on the other side, the opportunity for that pressure to go someplace it is not supposed to go is always there: through a bad seal. Similarly when an engine blows a head gasket and starts puffing gasses into the water jacket, or the water pump starts pushing water into the cylinders.....
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@Phantom-mk4kp Right. Youtube is for insults. Don't break the legacy.
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May also consider (I don't think it was mentioned) twin scroll turbos, which direct exhaust gasses at different convergence locations on the compressor wheel, depending on engine RPM.
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Free? ehhh. It's just utilizing an aspect of combustion that is otherwise ejected to atmosphere out of necessity. While heat naturally evacuates itself to a large degree, with the "enclosed space" between the top of the piston and the turbo impeller, there is some work being done by the piston shoving air against the turbine. It's minor compared to expanding gas/heat doing the work, but it's present. A turbocharged engine also benefits from a bit of "cushion" to the piston under what is normally the most violent (quickest deceleration) part of a piston's movement, the exhaust stroke.
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