Exhaust to noisey

[dal2litrefrogeye]

Hi all, got excluded from sprint today , exhaust to noisey ,it wasnt the end of the world I double drove with my wife in her Mx 5 , so my question really is any one use a silencing device of some sorts to get sound down on track days etc, mines a s b c with factory exhausts , and was making 114 db at 4500 rpm , any photes of how they fit or where you got it from etc would be helpfull , regards Darren

[andygtt]

repack the silencers as they will not have any wadding in them anymore, you should be 105-108 max with the std system.... other than that your looking at changing the design of the system or fitting additional silencers.

I got my sbc powered ultima down to 100db @5200rpm by changing the design of the exhaust adding extra length a balance chamber and having freeflowing straight thro silencers so you have plenty of scope to reduce sound if you really want to.

[Steve_D]

We have used 'supertrap' style end caps to get noise down but I would only suggest those for a ststic test as the back pressure is immense. A few years back someone else did this and changed a yellow rear clip to orange.

The Factory can supply a box that runs across inside the rear grill or you could have one made that fits on from outside just for track use.

Steve

[GTRMikie]

Steve_D said:

.....and changed a yellow rear clip to orange.

Steve

and melted everything under the clip!

[V8Dom]

had mine repacked last year by JP in Macclesfield...

94 db at 3000 rpm
98 at 4000(or was it 96??)

anyway, too quite so when the wadding started to melt 500 miles later I was well happy...

It will last a track day but not long term..

Dom

[peterg1955]

Have a look at Acoustafil, I know a lot of people using this stuff and it doesn't get burnt up so lasts much better than wadding or E-Glass

Edited by peterg1955 on Tuesday 5th April 09:29

[MarkWebb]

Having spent £3k last year on trying to get quieter. I drove the whole way to SPA on Sunday night arriving at 3.30am to get excluded from the track day on Monday for being 107db!
Never mind I had good fun driving and as a passenger in a Nissan GTR belonging to a good friend whose son was on track to be very near the lap record for that car when the heavens opened!
I met Swiss Tony there with his car which ran well for the first time until he snapped a throttle cable which ended his day! What a really nice guy he was, putting up with me chatting to him when I had nothing better to do.
His car with LS7 passed the noise test but still seemed pretty loud.