So why does sport mode sound differently?
05-13-2018, 02:03 AM
#1
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So why does sport mode sound differently?
I thought that sport mode sounds differently because symposer opens. I disconnected my symposer (so much better now), but noticed that sport mode still sounds different.
So I did an experiment - started a cold car and let it warm up to about 80% of where it stabilizes - at this temperature, the engine is completely warm but idles at the same 750RMP in both sport and normal modes (just above that temperature, sport idles slightly higher and normal slightly lower) and changed from sport to normal and back. The exhaust note changed noticeably both inside and outside, actually more so on the outside. The idle stayed the same, the symposer is removed and AFAIK, there are no flaps in exhaust. So what does it?
So I did an experiment - started a cold car and let it warm up to about 80% of where it stabilizes - at this temperature, the engine is completely warm but idles at the same 750RMP in both sport and normal modes (just above that temperature, sport idles slightly higher and normal slightly lower) and changed from sport to normal and back. The exhaust note changed noticeably both inside and outside, actually more so on the outside. The idle stayed the same, the symposer is removed and AFAIK, there are no flaps in exhaust. So what does it?
05-13-2018, 02:20 AM
#2
RL Community Team
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I believe it changes the engine profile - timing, boost, etc. - which affects the sound of the engine, both at idle and at throttle
05-13-2018, 12:57 PM
#3
Rennlist Member
I think it’s s combo of timing and cam phasing changes that do it. The VTG vanes also change pitch in order to increase shaft rpm at partial throttle and low load for better transient response with a slight hit to fuel economy as a result.