From my understanding restrictions in the
exhaust system are more beneficial at lower engine rpms (where
exhaust velocity out of the engine is low) in order to scavenge
exhaust fumes from the engine more quickly at low speed, however this becomes a bottleneck at high rpm (where
exhaust velocity is high) and
exhaust is exiting less freely than it potentially could. If that's true and the engineer/product manager/NPI guy assumes that the vehicle will spend most of it's life in 2-4K RPM it would likely have a more restrictive
exhaust than a car using the same engine that's expected to see the bulk of it's usage in higher RPM. I'm curious what the "ideal engine speed" the G70 has its
exhaust tuned for vs BMW.