Noise levels?

[9dreizig]

Anyone know what the db level of a turbo is running just a zork at the track?
I might be ru Ning at Latina later and they have a 91 db limit
Brian??

[TiberiusCassius]

Well, I have a DP11 exhaust and it has 104dB while running idle and 120dB while driving. Therefore, if you only have a zork tube I reckon that you wont make the 91dB limit...

Kind regards,
Dennis

[RarlyL8]

My street muffler which is pretty quiet at idle will not pass the 92dB limit on the track. Feedback from the racer guys has it at ~94dB. One of my projects, the Quiet Riot, has a 90dB goal that is proving difficult to meet without impacting performance and looking like you've got a suitcase strapped to your engine. You can only imagine what a zork puts out ...

[Richard930]

Hi Brian - would a wastegate muffler help meet the noise level restrictions without hurting performance? I love the sound of the wastegate dumping when I'm having fun on my own, but it certainly seems to add a level of noise well above the sound from the tailpipe that attracts a lot of attention when there are others around!

[RarlyL8]

Definitely. A wastegate muffler will be required for me to meet the 90dB goal, I just haven't figured out an elegant way to plumb it yet and not affect boost creep in high output engines. Any occlusion past the waste gate actually increases performance by putting back pressure on bypassed flow which in turn increases the boost level.