GT4 Static Noise Test

[Trikster]

Hi guys,

Got my first trackday in the GT4 booked up at Bedford end of next month where the limit is 101dB static -

Am reading mixed feedback in various posts as to what the GT4 is actually registering on the statics, anything up to 104dB, can folks post what they've been registering

We're taking the 987 Spyder up too that day (Mrs Tricksters first 'solo' track driving, so be warned ) - so will post some comparisons after the day for those who are interested

TIA

[gtsralph]

Best and easiest noise management mod is to fit downturn tips, reduces static and drive-by noise. GT4 doesn't have GT3's exhaust tip mount plate so you'll need to get a special part fabricated. I had mine done whilst I waited at https://www.infinity-exhausts.co.uk/index near Castle Combe but any competent exhaust shop can make up.

[mdianuk]

Most GT4's around 103db (without sport mode), 107db (with).

[Trev450]

Bloody hell that's loud. Why did Porsche build a track-focused car and make the exhaust so loud that it will struggle to get onto most UK circuits?

[Fl0pp3r]

Its pretty much the same with 7.1 & 7.2 GT3 in my experience...I find that if you explain (politely) to the noise tester that you understand its a little 'over' on the static, and that you've been round the track before and promise not to give it 'full beans' out of corners (ie keep your revs down/short shift) - they will let you on! Better that, than lose your booking fee and have to trudge off home empty-handed.

You know it makes sense

[BubblesNW]

mdianuk said:

Most GT4's around 103db (without sport mode), 107db (with).

Mine was 104 db at 5.5k static in sports mode at Oulton 2 weeks ago.

[Trikster]

gtsralph said:

Best and easiest noise management mod is to fit downturn tips, reduces static and drive-by noise. GT4 doesn't have GT3's exhaust tip mount plate so you'll need to get a special part fabricated. I had mine done whilst I waited at https://www.infinity-exhausts.co.uk/index near Castle Combe but any competent exhaust shop can make up.

Have you any pics - castle coombe a bit far out it if it does the job and they can recreate one and send it on that would be great

How does it attach? Was hoping the tailpipe ends were bolt on but looks like they are welded

[ChrisW.]

At Oulton I was 104 in normal exhaust setting but they asked me to run it up to 6000rpm --- which was too high.

At Cadwell Park I was 101 at 5500 ???

[BubblesNW]

Don't know what the reason is, or whether it actually works but I was told to drop the clutch when doing the noise test which lowers the db reading a little.

[gtsralph]

Trikster said:

Have you any pics - castle coombe a bit far out it if it does the job and they can recreate one and send it on that would be great

How does it attach? Was hoping the tailpipe ends were bolt on but looks like they are welded

I'm away from home so sorry but no access to pictures. The stock part comprises a cross tube that runs between the two back boxes, exiting from this are two rear facing tubes (reinforced with a bridging web) and the tips are fixed onto the two tubes. The whole assembly is a one piece wielded part as you noted. You need to have a part fabricated to replace the whole assembly with turn down tips instead of the OEM tips.

[ChrisW.]

I always dip the clutch --- no need to add gearbox noise

[braddo]

ChrisW. said:

I always dip the clutch --- no need to add gearbox noise

I believe it's the extra noise from the engine of having to spin the input shaft inside the gearbox (i.e. extra load on the engine = more noise) - for the same reason as people say to switch off the aircon.

I've been surprised to hear how loud the GT4s are when I've heard them at track days.

[HoHoHo]

braddo said:

ChrisW. said:

I always dip the clutch --- no need to add gearbox noise

I believe it's the extra noise from the engine of having to spin the input shaft inside the gearbox (i.e. extra load on the engine = more noise) - for the same reason as people say to switch off the aircon.

I've been surprised to hear how loud the GT4s are when I've heard them at track days.

I used to do that on my 997 C2S for Goodwood and it made all the difference and down to under 100db

Also try not to be spot on the rev range they want, invariably the tester will simply be poking his head through the window and never gets a totally clear view

[Trev450]

If the car is borderline to start with, then you are always going to be on edge that it could fail and you've wasted a day. I know from experience that dipping the clutch, having the engine up to temperature, A/C off, etc, all helps, but ultimately for peace of mind you need to have a 'decibel killer' of some shape or form.

[gsewell]

So how come Porsche in the wisdom make a track day car that is almost too loud to go on track???? That borders on the definition of fit for purpose.

[HoHoHo]

gsewell said:

So how come Porsche in the wisdom make a track day car that is almost too loud to go on track???? That borders on the definition of fit for purpose.

I would have thought that depends on the track.

Goodwood for example have different noise limits for different track days with the highest being 105db, with sub 100db on other days.

[bcr5784]

Quite a few days are 98db limit, which sounds difficult to achieve.

[BubblesNW]

bcr5784 said:

Quite a few days are 98db limit, which sounds difficult to achieve.

Donington is a 98 db limit on drive by which is very different to 98 db static. Also noticed that Anglesey is 95 db in the summer months and 105 db at other times, maybe to appease the holidaymakers in Rhosneigr.

[boxsey]

gsewell said:

So how come Porsche in the wisdom make a track day car that is almost too loud to go on track???? That borders on the definition of fit for purpose.

To be fair to Porsche they refer to the GT4 (and anything similar) as a road car that you can take to the track and therefore it is fit for purpose. And it's not as if there is some standard noise limit for tracks that they could work to when developing a car.

[Mustangs]

Thrown off Brands recently. Wont bother going back, that place has become a joke