Side Exit Exhaust

[Joespeeder v2.0]

Hey All,

 

I'm about to order the side exit exhaust for my Zetec minus the cat. I was wondering about noise levels both for me and for the track. Any idea on db levles on the left side of the car for a side exhaust Zetec?

 

Waterford Hills has a 75db limit measured from the left side of the car. You can thank the local courts and people bulding houses next to a race track only to figure out that cars make noise for the low limit.

 

And so it begins.... Upgrades!!!

 

 

Joe

TheCaterhamProject.com - Build site with photos here

 

Edited by - Joespeeder on 18 May 2006 20:00:57

[Paul McKenzie]

75dB is the noise a cat (pussy type) makes when it crosses the street at the dead of night...you need to find somewhere diffferent to play

 

Paul

[Andy Best]

We did some adhoc testing earlier in the week with a range of cars and exhausts the only cars that registered below 75dB were the ones in th epadock with the engines off ❗

 

Seroiusly most were in the 90 -100 dB range I gues you will be struggling to make a 75dB limit unless they use a different measure over the pond, greater distance and low engine revs drop the figures but you will need to have the car quite away from the meter.

[SLR No.77]

Check this HSE Publication

 

75db is the noise created in a primary school classroom

 

If you're taking the 7 you'll need to push it ☹️

 

Stu.

[ashaughnessy]

The 75db depends on how it measured, surely? They might be measuring it from half a mile away.

 

As for the exhaust - you've either got one already that you want to replace or you're thinking of some alternatives. What are the alternatives? If you don't have one and don't have any alternatives then the caterham item will certainly be quieter than nothing

 

Anthony

[Tim_H]

Take the Zetec out, and install a big electric motor and a row of Lead Acid cells, and you could be the first Eco Friendly Seven. And very quiet too! 😬

 

75DB !, I bet tyre squeal is louder than that!

 

Tim(L7 EVN)

[Sheds Moderator]

You will never get 75dB under UK testing conditions. Noise does diminish as the distance squared though so if the USA method is further away than the 50 cm (?) quoted in the UK then it *might* work.

[Joespeeder v2.0]

Morning All,

 

After seeing your posts and feeling really dumb, I went to the WH's web site and according to the rules it's 75db at the property line which my guess is about 30 yards away. Waterford installed a giant noise fence this past year so that should help things. Sorry to be misleading, I've never had a car that was close or ran a side exit system that points toward the meter, so I've never worried about the limit before. I've got some emails out to find out what really passes as too loud there. I'll let you know what I find out.

 

It would be a shame not to run there. Sterling Moss is reported to have called it the "Most challenging short road course in North America" It's great fun and better yet only 1/2 an hour from my house. It's 1.3 miles and 13 corners with evevation changes.

http://video.google.com/videoplay?docid=-3514282252117912619&q=waterford+hills

 

My concern is ear comfort. Should I expect the switch to side exhaust to be a major pain in my...ear? I have visions of unmuffled RX7's ouch....

 

I currently have the standard Caterham Zetec rear exhaust with cat. I was going to get rid of the cat and go to the standard Caterham Zetec set up which is a side exit.

 

 

 

Joe

TheCaterhamProject.com - Build site with photos here

 

Edited by - JoeSpeeder on 19 May 2006 14:45:39

[Tim_H]

30 yards away, - hm.... Probably can be quite loud then, say 100dB

 

Also Induction roar can be a big noise factor too, especially with high revving engines.

 

Tim(L7 EVN)

[tom7]

Unmuffled rotary engines are among the loudest you will ever hear on a track.

My side exit is measured at 98dB, with you helmet on its no problem, if you are touring, ear earplugs