Track-friendly 3.4 exhaust options

[tob_today]

I had to cancel a track day for my 3.4 C2 because my current gundo'd Dansk Sport set up was borderline on the static noise restriction limit (105 dB). Post here: http://911uk.com/viewtopic.php?p=1617803

So now I need to rethink my exhaust to give me best of both worlds:

(1) Fun driving around normal roads = nice & sporty
(2) Safely under track day dB limits = quiet as possible

Of course, zero drone in both.

Seems I need a switchable valved cat-back system. However as always it's super hard to properly evaluate & compare these before pulling the trigger. For sure no 200 cell cats.

Options seem to be:

- PSE Factory Sport Exhaust, not sure how good this is on 3.4
- Top Gear
- Sypder
- DesignTek
- Cargraphic

Anyone have good experience using any of these on both track noise tests and regular use?

Any other recommendations?

 

[Alex]

77Szymon on here bought a valved system a couple of years ago which seems pretty good. Was well under a£1k.

 

[Alex]

Think the spyder one may be the one 77Szymon has:

 

[Guywilko]

Ebay stainless manifolds. Standard cats. MY2000 C4.

Designtek sports supremacy too loud.

Designtek sports passes scrutineering at oulton park

 

[Griffter]

Factory PSE on my 3.4 always sounded brilliant to me and was (IIRC) 95dB at Castle Combe. It's not manual switchable though, so for a noise test it is what it is. Having said that I think it switches to louder at 30mph so static noise tests are ok. I wasn't picked up by any drive-bys.

 

[tob_today]

Factory PSE on my 3.4 always sounded brilliant to me and was (IIRC) 95dB at Castle Combe. It's not manual switchable though, so for a noise test it is what it is. Having said that I think it switches to louder at 30mph so static noise tests are ok. I wasn't picked up by any drive-bys.

Thanks Griffter, although I thought PSE is manually controlled by via dash control switch? Is that not correct?

As shown here:
http://www.carnewal.com/products/996/p96059/PSE-Factory-Sport-Exhaust

 

[Griffter]

Factory PSE on my 3.4 always sounded brilliant to me and was (IIRC) 95dB at Castle Combe. It's not manual switchable though, so for a noise test it is what it is. Having said that I think it switches to louder at 30mph so static noise tests are ok. I wasn't picked up by any drive-bys.

Thanks Griffter, although I thought PSE is manually controlled by via dash control switch? Is that not correct?

As shown here:
http://www.carnewal.com/products/996/p96059/PSE-Factory-Sport-Exhaust

It is on some - it was on my Boxster Spyder and maybe on the 996.2 - but not on the factory PSE on 996.1 as far as I know.

 

[hazzarelli]

Thought I'd just update here with my recent experience..

Top gear headers/ 200cell Xpipe / mild back boxes were fitted last month

No problems so far with track days (lyyden hill 100db, brands hatch 98db)

My reading at 5krpm was 93 db which suprised me as I thought I'd be sailing a bit closer to the wind.

If anyone is considering a new exhaust I would highly recommend the above. No louder on motorway/ around town but screams when you open the taps above 5k rpm. Much more revvy now too - the 3.4 seems even more eager to go right up to the redline, whereas with the original exhuast 6500 seemed like the appropriate time to shift up.

Hope this helps somebody!

 

[coullstar]

Thats the same set up as mine, TG mild boxes do give the low end quiet but noise up top and the 200 x pipe adds a little bit more as well.

I gundo hacked mine with a fairly small pipe as wanted it just a tad louder overall but Id say that set up gives the best of both. Always found the switchable ones either too quiet or too loud in either mode.

 

[Lj911]

this is good to know, i have the exact same setup, mainly did it so i'd pass noise tests at trackdays.....the only days I've since been to have had no noise limits so I've not found out for myself yet!

Was running the car with top gear manifolds and 200 cell cats (std style not x-pipe) with gundo'd standard porsche back boxes....sounded bloody epic but it was loud!! The 200 cell cats make quite a difference to volume!

Putting the top gear 'mild' back boxes on has quieted it down a fair bit.

i'd say the car actually sounded best with full std exhaust with the gundo'd back boxes, just sounded rich and somehow right! but i have some weight reduction goals so hence the change, plus trackdays so had to go quieter :sad:

 

[tob_today]

Thanks for sharing. Would be nice to get some freer flowing with the 200 cell cats, buy yes does add to volume usually without the nice sound modified rear boxes can give. Cats and opened rear boxes would be best of both worlds but is very loud and definite no-no for most track days.

So seems best non-OEM option for track day compliance might be either 200 cell + milds giving freer flowing performance, or switchable if want most / best sound when not on track. As always in life, it's a trade off decision.