Is it really that loud?

[noodleman]

I'm finally getting round to booking a track day so I've borrowed a decibel meter to see which tracks I can go to.

I measured at @ 1m from the tailpipes, with the meter pointed directly at the pipes at 5K rpm.....

109db

Is the meter dodgy? The car is a standard S1 with an unknown exhaust (I think it's a Janspeed). I assume that the cat is still there as it sailed through the emissions test and everything else is standard (airbox, throttle bodies, suspension etc).

Is 109 realistic with ANY back box? Am I measuring incorrectly?

[Phil-CH]

That is rather loud. Does it still have a cat?

[ptp170]

Isn't it 0.5m from the exhaust at 45 degrees???

Chris

[Esprit]

My new 'Zige has a decatted Janspeed and it's EFFING loud (glad we don't have noise limits here to stifle us!)... it's a LOT louder than my old Elise was with Hurricane and decatted Larini system.

[noodleman]

I assume the cat is still there although I've never looked. So much of the car is standard that I'd be surprised if the previous owner had de-catted.

I presume I'd have to get the undertray off to see?

[worldwidewebs]

How old is the silencer? Their noise reduction capability does drastically drop off with age, hence why lots of racers use repackable ones.

[noodleman]

I'm not sure. Somewhere between 2 and 7 years old.

I'm not being very helpful am I?

[S Works]

Could be the silencer has blown all it's innards out.

[noodleman]

Presumably this would mean I need a new silencer?

[S Works]

noodleman said:

Presumably this would mean I need a new silencer?

Probably yes, if it's that which is knackered. If you don't have a decat (it's very obvious if you do, just drop the undertray at the back and have a peek in) then it's likely the box has seen better days. ~£300 for a new Janspeed.

[piooly]

I thought the rule was about a foot and a half away from the pipes at a 45 degree angle...?

Thats what they do at bedford.

[S Works]

piooly said:

I thought the rule was about a foot and a half away from the pipes at a 45 degree angle...?

Thats what they do at bedford.

Well, that's one test (static). You also have to pass the drive-by tests while you're on track, where generally you'll be even louder.