Thread: Turbo Boost PSI
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      05-06-2012, 09:51 PM   #40

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Originally Posted by 1SerieStud View Post
Incorrect. Boost is a measure of air compression, inside the engine's cylinders by the pistons. Backpressure has nothing to do with it, in fact, in turbo-charged applications we like to reduce backpressure in exchange of exhaust flow, in order to make the system more efficient and less restrictive.
Boost does not refer to the pressure in the cylinders, or to compression. It measures the pressure in the manifold, which represents the backpressure building up as intake flow out of the turbocharger exceeds flow into the cylinders. It is not the same kind of backpressure that is seen on the exhaust side, which can be detrimental.

All other variables held equal, a port and polish or any other work that improved flow through the intake valves into the cylinders would decrease boost pressure and increase horsepower.