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sorta. The restriction isnt just the pipework. Its flow thru the cylinder head, exhaust, intake and everything else. And with a larger turbo, with larger hotside and wheels, the exhaust side becomes much freer flowing, and back pressure falls off, and you flow more air.
A 350hp K03 car might run 20psi, and a 450hp K04 car might run 18psi. The exhaust on the K03 side is super restricted and your adding huge amounts of boost to overcome ever increasing back pressure... with the K04, suddenly your making 100hp more with less boost.
If you consider what happens on a naturally aspirated engine when you fit a nice exhaust manifold, decat and full exhaust system, you get more power despite having not changed the intake, or the pressure being fed into the engine.
A turbocharger is a VERY large restriction in the exhaust pipe, and fitting a larger one has the same effect, but because its such a restriction, the effect is very large in comparison to the small gains you get on an NA engine.
Its for the same reason that turbo cars benefit from huge unrestricted downpipes and exhaust systems. As any backpressure after the turbo is multiplied thru the turbo back towards the engine.
A 350hp K03 car might run 20psi, and a 450hp K04 car might run 18psi. The exhaust on the K03 side is super restricted and your adding huge amounts of boost to overcome ever increasing back pressure... with the K04, suddenly your making 100hp more with less boost.
If you consider what happens on a naturally aspirated engine when you fit a nice exhaust manifold, decat and full exhaust system, you get more power despite having not changed the intake, or the pressure being fed into the engine.
A turbocharger is a VERY large restriction in the exhaust pipe, and fitting a larger one has the same effect, but because its such a restriction, the effect is very large in comparison to the small gains you get on an NA engine.
Its for the same reason that turbo cars benefit from huge unrestricted downpipes and exhaust systems. As any backpressure after the turbo is multiplied thru the turbo back towards the engine.
