Okay I took vet757's advice and did my best to record the sound. It's with my iPhone and iOS wouldn't let me upload it in HD, but the sound still comes out I think.
https://youtu.be/ch9WA3ygXwg
One thing I noticed while recording this, which I didn't before, is an engine noise while idling. Can anyone tell me if this is normal?
Anyway, I start accelerating and you'll hear the exhaust and engine sound the way it's supposed to. But then at higher gears when I try and go up the bridge you can clearly hear the groan.
Interested to hear what you guys think.