|
boxster tends to have pretty quiet exhaust, and the engine compartment is well insulated (close to the driver in a mid-engined car, so noise and heat would be an issue without insulation).
most of the sound you typically hear from the car is the intake, which right behind the driver's left ear. as the engine rpms increase the car tries to draw more air though that intake and get gets louder. it's especially obvious as the cams 'roll over' that is, at around 4000 rpm the cams change profile (vario-cam, or vario-cam+ depending on the year of your car) and some flappers open on the intake tubes in an effort to flow as much air as possible.
so, if you are spending more time at 4000 rpm than 2000 rpm, and if you have the top down more, than the car will sound louder.
not sure if that is your issue, however, if it sounds louder at idle and idle is rougher. the first step i would take is to determine what the 'loudness' is - is it intake, exhaust, or just things rattling and clacking together. that will help determine where to look further.
|