W204 C63 Silverstone Track Day Noise Limits

[W204_C63]

I've got a 2013 C63 with the P31 performance pack (not that I expect the performance pack to significantly change the noise levels).

I'm planning my first track day at Silverstone. Has anybody tracked their C63 recently at Silverstone with the current 102dB noise limit?

I think the exhaust is stock, but I bought it used, so not 100% sure (had a fresh MOT and new cats before I collected).

I bought a sound meter from Amazon and registered:

- 93dB @ 4,500rpm (0.5m at 45 degrees from the rear bumper)

- 101dB @ 6,500rpm (10m directly in line with the back of the car)

(oil temp warmed to > 80C before both tests)

With the 101dB so close to the drive by limit, I'm somewhat nervous about the noise levels - last thing I want is to spend £400 (track day + insurance) for 5 laps and get sent home. I also appreciate the limitations in my test:

1. £16 Amazon sound meter probably not the most accurate device (although going to better than using mobile apps)
2. Didn't do a proper drive by test (just made an educated guess about the 10m distance @ Silverstone). Probably best not to do drive by simulations on public roads.
3. Since tests were completed on my driveway, sound may have reflected off the house/garage
4. For drive by, the microphone unlikely to be directly behind the car as it will need to be off the track somewhere.

I've seen a few older threads, notably this one, but nothing that mentions Silverstone directly (which being so close to the limit, is fairly important as distance/positioning of the noise equipment will make quite a difference).

I'm hoping an existing C63 owner might be able to share their (recent-ish) experiences on track at Silverstone and/or if anybody can recommend some inserts/baffles that fit a C63 tailpipe? (or other tips to reduce the noise).

Any other "first track day" tips also appreciated.

Thanks.

[brillomaster]

The best way to know how loud your car will be, is go to a local track with a trackday on and ask them to noise test it. however, drive by noise test of 102db is really pretty high - bedford for example, the drive by is only 87db!

i'd have thought 102db drive by would be about 105db static, which is really quite loud.

As for general trackday advice, theres loads of info on EVO site, these two pages should get you started:

https://www.evo.co.uk/trackdays/features/234398/pr...

https://www.evo.co.uk/advice/19815/track-days-ever...

[W204_C63]

Thanks! I've checked those out and I think I'm in pretty good shape.

Definitely a few tips I hadn't considered and I've taken onboard.

[Rob_R]

I'd think, even with a slightly modified exhaust, a W204 C63 won't be pushing 102 drive by. If you are on a standard exhaust then you'll be absolutely fine.

[Mark83]

Mine was fine at Bedford although they asked me not to run in Sport+.

Silverstone isn't as strict as Bedford.

[W204_C63]

Thanks all for the advice. Posting an update because I hate threads where somebody asks for help and then disappears without any feedback (especially if you find that thread on google!)

Since the post, I've had the car serviced and found out the secondary cats have been replaced with sport cats.

The track day was yesterday (26/10/2020) and there were absolutely no issues with noise. I ran the car in manual all day and must have been below the 102dB noise limit.

I did manage to do a drive by test on a national limit road (60mph in 2nd/3rd gear) with a helper standing about 10m back in the entrance to a farmers field where my sound meter registered 94dB.

I did get some cheap baffles, just in case, but didn't need to use them. I did a test fit at home, using the bolts as grub screws and they seemed to fit OK, however the thread in the baffles wasn't brilliant so I used a couple of nuts to make them more secure.

Thanks again for the help and I hope this info is useful for someone in the future.

Edited by W204_C63 on Tuesday 27th October 09:56

Edited by W204_C63 on Tuesday 27th October 09:58