How loud?

[GarryM]

I’ve just had confirmation through for my track day at Hullavington Airfield. No doubt due to the recent fuss about noise at these events, the noise limit is now 100dB(A) at 0.5 metres and at 3/4 of maximum revs (down from 103dB). It says this limit is rigidly applied and if concerned about failing - don’t turn up! Great! I have never thought about checking and was comfortable that my car was below 103dB but I am not at all sure about 100dB.

So… anyone know how loud a Griff 500 in good mechanical condition with standard exhaust would be?

TIA

[Leadfoot]

How old is the car (will get noisier as it gets older)? Mine is '96 with 30K & registers 97db on Goodwoods noise meter (made 96 the first time it was tested). If you've a standard exhaust it won't be anywhere near 100db so don't worry.

[manek]

Funny you should ask that -- I'm convinced my sports exhaust has got louder as it's aged. It's now two years old and sounds much fruitier than it did.

Not sure why...

[Nacnud]

Well known problem on motorbikes; the packing gets clogged up with sh1te and no longer does it's job. Becomes more like a straight through pipe than a silencer box.

I've taken the sports exhaust off my bike because it's recently got way loud and also lost the lovely bass note I liked (and MoT soon).

There are repacking kits available for bike exhausts but I've never heard of one for a car.

[GarryM]

Thanks for the replies. Mines a '96 vintage with 13750 miles so I guess should be pretty close to yours Leadfoot. What a relief - didn't fancy the idea of driving all that way (in what looks like will be pouring rain )just to be told to go away again!

[350matt]

Make sure that they test it at 45° to the tailpipe as well as per RAC directions, this makes a big difference. I recently measured my wedge (4ltr tuned, no cat, one silencer) and that came out at 100dB at 4000Rpm.
Another tweak is to only dial up 3000Rpm or so and claim that the engine only goes to 5500Rpm.


Matt

[RolexBlue]

I have a ¾ sports exhaust which sounds awesome it peaks at 106dBa @ 4500rpm and I have had to invest in some mufflers (thank you Tower View Racing) which have knocked things down to a more track day friendly 98-100dBa.

Paul

[GarryM]

Measured 99.5dB at 4500 rpm. Limit was 100 so nice to think I was a loud as I could be without being over!