Exhaust question

[cobalt911]

Hi folks,

Quick one. I used to have a 996 with the sports exhaust and it sounded great...lovely low bellow! In comparison my 993 is a little weedy although I do like the improved induction noise now I have drilled suitable holes in the airbox []

There seems to be a few silencer boxes on the market with the cargraphic and RSR systems standing out. If I want a good growly sound what is the best option in folks opinion?

Cheers,

Mark

 

[Shaun Leahy]

Mark

I sat in a car with RSR's and then compred to mine with LPMMs. RSRs: noticed a trace of reasonance but was not hapy with the high tone of the sound, though it does have a rasp.

My favourite: Based on a standard pair of silencers, with a bridge pipe welded between the in/out pipes, the LPMM mod (see Rennlist/Youtube) has a lower grumble than standard, is noticeable as a throaty rasp at idle. Between 2500-3000 is a wonderful growl (imagine an angry bear saying G R O W L). When cruising along, there is not much notice of the noise as exhaust gases do nto so much bypass the silencers; that changes when you increase relatively small amounts of gas pedal. My car had far less resonance than the RSR car above and I love the idle noise and the acceletaion noise. Occasionally you will get decel pops from it. One day soon I will get it on digital.

I think this LPMM solution solves the weedy exhaust noise problem.

Getting there: find a welder with some stainlesss about 1.5" -2" across, so matching approx the diameter of the in/out pipes and let him loose on your silencer. [no point with anti-rust paint on the silencer as it will not stick to a smooth surface.] Note: standard silencer boxes are not best qual stainless and you will need TIG welding (I believe). The larger the pipe the deeper the noise. Cost: say £150 tops; unbelievable value. A 993 guy at a Rennlist meeting in SE London was miffed at his own H&S system in comparison. I do not guarantee any performance change but oyu may want to clean/repace an old O2 sensor to ensure the whole system barks.

If you do not like this mod then make sure your blood is still moving.

 

[sidned]

Supercups! I have first generation ones with removeable baffles. Believe me when I say they are LOUD without the baffles!

I only have a sound byte when stationary, just blipping the throttle with the baffles in : http://media.putfile.com/Supercups-outside

I must get a clip with the baffles out!

 

[M030]

ORIGINAL: Shaun Leahy

: find a welder with some stainlesss about 1.5" -2" across, so matching approx the diameter of the in/out pipes and let him loose on your silencer

Check your bypassed exhaust in 1-2 years from now and you'll see that the welds of the bypass tube will start to crack or already have been broken off.
This because of the enormous heat difference between the in- and outgoing pipes.

 

[jboult]

Mark,

I had Supercups on mine, but the previous owner had lost the turn downs. Great noise, but VERY loud - especially on a Targa. In the end I replaced it with the standard system, although I do partly regret it. Getting hold of a pair of turndowns first might have been a better way forward.

Anyway, if you're interested I still have the Supercups sitting in the garage. Only on the car for 12 months, all reasonable offers considered!

Cheers/John

 

[Shaun Leahy]

M030
I bow to your knowledge on welding. I would be upset at replacing a clutch, or even disty caps every 2 years, but am not worried about redoing with something slightly larger, dependent on your crack which is still to appear.

Just replaced my original modified silencers, after a shunt in the rear. There were no cracks visible in the originals, though I did nothing further than an eye check.
Cheers