[Bee Pee]

Folks,

Had a dilemma at a Goodwood trackday recently with my e91 335i 6MT.

I have Birds p/back controller [Procede V5], AR catted DP's and OEM performance exhaust.

On either map 1 or 2, the car wouldn't pass the noise test in the pits. Didn't fancy the local fix of the baked cans clamped to the tailpipes so tried again with stock map [#0] and it passed so went out to play.

Had a great day and posted faster times at full chat in stock map than short shifting in map 1 or 2.

I'm well happy with my setup but do got more rasp/volume when running boosted maps. Ordinarily that doesn't bother me but I'm interested in any advice on getting fix for the rasp on OEM performance exhaust so as I can go play at Goodwood in boosted maps and not fall foul of noise police in the pits.

Thanks in advance,

Dave

[ZondaF355]

try adding resonators if you dont have any...

[M3-FAST]

Are they monitoring noise all day then at these trackdays?

Any of the ones I have attended just bring the microphones out as you join the queue for the sighting laps to ensure everyone gets tested - once the little coloured spot is applied to the windscreen, that is normally it? I have never been tested again later in the day .

I would personally turn to the stock map for noise tests and then switch to the boosted maps once out on the track - I doubt anyone would ever notice, especially as there is a higher chance that several cars would be passing the pits together.

[Giff]

They monitor your noise level as you drive past the pits nowadays too, local councils seem to be causing quite a few problems.

[Bee Pee]

Guys

Thanks for the comments so far.

Extra resonators - has anyone fitted additional silencers into PE?

Noise tests - upping the boost after pit checks is risky as I saw 2 cars get barred for the rest of the day after just one outing. Not sure if there are micas abt the track.

[m1bjr]

Odd.
I ran a Bastuck + cones on otherwise oem system and a tune, and was well under level at the events I attended.
As they are TUV approved as per the Bastuck I am very surprised.
Maybe it has a defect?

[Bee Pee]

TUV approval likely to be based on stock DP's as opposed modded catted Dp's.

Gradual throttle application seems to be ok. Stamp on gas and it screams like a banshee. So coming back on the gas exiting the corner is fine on the track. Once front wheels are straight and WOT applied it rasps like crazy.

If I can beat the rap then I think I've found my solution.

[phil200tdi]

Post some videos

The rasp on mine is getting annoying too. AR catless but otherwise stock exhaust.

Plan on getting a Bastuck exhaust which I hoped would solve the problem. The e90/91 exhaust has resonators already so I guess they aint up to the job.

[Bee Pee]

On OEM PE for e90/e91 you lose the silencer in the mid pipe section of the standard exhaust and gain a crossover instead, similar to the e92.

Stock or boosted, my setup sounds great as a daily driver based on the fact that opportunities to use WOT for any lengthy periods on public roads is limited.

I might struggle wrt a video but will see if I what I can do.

[fastloop]

What was the noise limit on the day? AFAIK Goodwood have various limits depending on the size of the group and it could have been a day where the limit was quite low. Heck last I was there I saw a Ferrari 599GTO and it sounded absolutely amazing at full chat.

[Bee Pee]

In the pits 98db near exhaust at above 3/4 throttle + out on the circuit 96db drive by.

[m1bjr]

Originally Posted by Pave Dew

opportunities to use WOT for any lengthy periods on public roads is limited.

Not in Somerset it's not, cum down 'yer boy

[Hotcoupe]

Originally Posted by 335rocks

What was the noise limit on the day? AFAIK Goodwood have various limits depending on the size of the group and it could have been a day where the limit was quite low. Heck last I was there I saw a Ferrari 599GTO and it sounded absolutely amazing at full chat.

Bang on Fella.

Goodwood noise limits:

NOISE RESTRICTIONS

Any vehicle to be used on the Circuit must pass a noise test on the day. Depending on the format of the day it should not exceed 98dbs or 105dbs at three quarters maximum revs when measured at 0.5metres from the exhaust, and either 96db or 101db, measured at 10m drive-by. Refunds cannot be offered should your car fail.

[fastloop]

Originally Posted by Pave Dew

In the pits 98db near exhaust at above 3/4 throttle + out on the circuit 96db drive by.

Did they tell you which limit you exceeded and by how much? Last I had mine tested at Brands it was around 95dB static with AR DPs & Bastuck exhaust.

[Bee Pee]

Originally Posted by 335rocks

Did they tell you which limit you exceeded and by how much? Last I had mine tested at Brands it was around 95dB static with AR DPs & Bastuck exhaust.

No, no actual dB value only that it failed in the pits 1st time around [map # 1]. They offered me the baked bean can bolt-on option. I said let me think abt it. Whilst thinking abt it I switched to stock map and went for the retest. This time it passed.....

[Bee Pee]

Originally Posted by m1bjr

Not in Somerset it's not, cum down 'yer boy

Thanks for the invite, I get down to Somerset a couple of times a year to visit friends on their farm just west of MInehead.

They hear me coming sure enough, so much so they walk to the end of the farmyard and have the gate open timed for my arrival.

My west country chums are used to it though. Over the years, I have graced their farmyard with a string of sweet sounding motors incl 2.5ltr Triumph Vitesse mk2 and a TVR V8s.

You are a lucky chap to reside in such a great part of the country.

[Bee Pee]

Update

Meet Raj from Profusion Customs and hatched a plan to install hi flow resonated x pipe in place of the oem PE x pipe to lose the rasp.

Raj seems like a top bloke so once done I will feedback on if the above has fixed my problem.