Can't Reliably Pass 105dB Static - Options?

Can't Reliably Pass 105dB Static - Options?

Author
Discussion

ukkid35

Original Poster:

6,138 posts

172 months

Monday 21st July 2014
quotequote all
I'm probably between 105 and 106, depending on weather/surroundings/tester etc. Other than Anglesey and The Ring, what are my options?

(The tailpipes on my new back box are too large for my track day cans)

gruffalo

7,509 posts

225 months

Monday 21st July 2014
quotequote all
What size tail pipes do you have?

Robert Elise

956 posts

144 months

Monday 21st July 2014
quotequote all
I have watched Martin squeeze his TiVo thru noise with two huge cans attached to his exhausts, only to then drive 10m remove cans and join the opl.

NB TiVo is autocorrect...

QBee

20,904 posts

143 months

Monday 21st July 2014
quotequote all
Put the old back box on for track days?
Find some insets that fit?
Cerberas have wider tail pipes - hence the Gruffalo question.....

gruffalo

7,509 posts

225 months

Monday 21st July 2014
quotequote all
Paul, I have some 3" track cans that I don't really need any more, mine now normally reads about 98db.

As you live about 15 miles from me if they fit your car I am happy to share them.

ukkid35

Original Poster:

6,138 posts

172 months

Tuesday 22nd July 2014
quotequote all
gruffalo said:
Paul, I have some 3" track cans that I don't really need any more, mine now normally reads about 98db.

As you live about 15 miles from me if they fit your car I am happy to share them.
Thanks Martin, that's very generous, unfortunately I've just measured the tailpipes and found that they are 3 1/2" OD.

grahamn

1,777 posts

233 months

Tuesday 22nd July 2014
quotequote all
Hi Paul, where abouts are you. I have some that fit my SP exhaust that may fit yours, you are welcome to try them.

ukkid35

Original Poster:

6,138 posts

172 months

Friday 25th July 2014
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grahamn said:
Hi Paul, where abouts are you. I have some that fit my SP exhaust that may fit yours, you are welcome to try them.
Hi Graham, not sure whether you got my PM, but thanks - that would be great. Hope we can meet up again soon. Cheers - Paul

ukkid35

Original Poster:

6,138 posts

172 months

Saturday 26th July 2014
quotequote all
How about a couple of these shoved up my tailpipes?



http://www.summitracing.com/int/parts/cci-3di35l/o...

gav dunn

291 posts

175 months

Sunday 27th July 2014
quotequote all
hi, we use to have the same problem with ferrari 355,we put a pair of super traps on, never had an issue since! good luck.(available from demon tweeks)

LFAwhoosh

32 posts

133 months

Wednesday 30th July 2014
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You could also splice a speedo healer into the signal wire to your analogue rev counter to slightly change the rpm the noise test is carried out at. It's cheating but if 3000rpm vs 4000rpm makes a difference this is another way to do it.

ukkid35

Original Poster:

6,138 posts

172 months

Friday 17th October 2014
quotequote all
I didn't realise pipe expanders existed, without it I wouldn't have been able to smooth the dents in the tail pipes, allowing the inserts to fit.







That should shave off 2 or 3dB, enough to get me under 105.

As a pair they are rated to 500bhp, so hopefully no loss in performance either.

ukkid35

Original Poster:

6,138 posts

172 months

Wednesday 31st December 2014
quotequote all
For anyone else in a similar position, another option is Silverstone. I didn't realise that there was no static noise test until going a couple of weeks ago. Sadly didn't get to drive as I was on the reserve list, but plenty of PAX laps, and several cars were significantly loader than mine.

firewallguy

192 posts

150 months

Friday 9th January 2015
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Cheers, I'm seriously considering getting a track-day in at Silverstone this year, so will hopefully get by with inserts rather than the power-sapping ACT cans.

ukkid35

Original Poster:

6,138 posts

172 months

Friday 9th January 2015
quotequote all
firewallguy said:
Cheers, I'm seriously considering getting a track-day in at Silverstone this year, so will hopefully get by with inserts rather than the power-sapping ACT cans.
Those track day cans strangle the engine above about 5k.

Interestingly when I was at Snetterton last month the MSV guys asked me what the red line was, I said it's the V8 so about 6k, expecting the usual 4.5k noise test. They decided to look it up on their list and then asked me to hold 5.4k!! By some miracle it passed at precisely 105dB without the inserts.

b0rk

2,289 posts

145 months

Saturday 10th January 2015
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Silverstone is 102dB drive by all automagical unless you go for their traditional may bank holiday date when it's 90dB drive by. The main meter is on the wing pit building wink

Spa is also 103dB drive by and 107dB static. drive by is measured from the F1 pit complex.

ukkid35

Original Poster:

6,138 posts

172 months

Sunday 11th January 2015
quotequote all
b0rk said:
Spa is also 103dB drive by and 107dB static. drive by is measured from the F1 pit complex.
Thank you.

My experience of the Spa static test has been quite varied: sometimes there has simply a visual inspection and your car and it passed if it wasn't radically modified, on other occasions there was a physical static test at the declared 3/4 rev limit.

gruffalo

7,509 posts

225 months

Sunday 11th January 2015
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firewallguy said:
Cheers, I'm seriously considering getting a track-day in at Silverstone this year, so will hopefully get by with inserts rather than the power-sapping ACT cans.
I ran the ACT track cans for many years, sap a little power from the very top end but only at the sort of revs that are just not worth using as you are way past peak torque by then, they also improved mid range torque quite a bit so net neutral I would say.


Drumroll

3,738 posts

119 months

Sunday 11th January 2015
quotequote all
Please guys don't try and cheat the dB limit for any track. All it does is give more ammunition to the "lets get this venue closed" type. Modify you car/bike so it meets that tracks requirements.

QBee

20,904 posts

143 months

Monday 12th January 2015
quotequote all
gruffalo said:
firewallguy said:
Cheers, I'm seriously considering getting a track-day in at Silverstone this year, so will hopefully get by with inserts rather than the power-sapping ACT cans.
I ran the ACT track cans for many years, sap a little power from the very top end but only at the sort of revs that are just not worth using as you are way past peak torque by then, they also improved mid range torque quite a bit so net neutral I would say.
Mid-range torque is far more useful, IMHO. Getting out of corners quicker without having to change down to the dreaded second gear is where it's at for me - second on my car is a looooong way below third in ratio terms, which can sometimes result in an interesting rear axle lock up if the gear is grabbed and the clutch ham-footedly dumped. It tends to result rather swiftly in an exit stage right/left, followed by a bear recovery truckeekirked