Rassel

Does anyone have experience with using muffler by-pass and K-24 Turbos?

I wouldn't mind the Turbos to kick in, a tiny bit earlier. I can't really figure out why, but somepeople mentioned CEL problems with by-pass pipes. Perhaps this was with cat. by-pass?

If it would be a good combo, would my twin-exhaust pipes fit somehow?

Cheers

(Yes, I've done the search )

vrus

I had this exact setup on my 993TT..

I had the FVD K24 Race turbos, FVD Sport Cats, Muffler bypass pipes. This combination was very loud at idle with a deep rumble. Believe it or not, while cruising it actually became quiet.

It was the loudest when the car was first started. As it came up to operating temperature, it quieted down a bit.

You will set off all the car alarms as you drive by though.

Oops.. Almost forgot to mention the most important thing of all; it made AWESOME power and the turbos spooled instantly!!

ScottMellor

I have FVD 24s, FVD CAT bypasses and TEchEFX mufflers or muffler bypasses. With the mufflers on it is not too loud at all. Turbo response is better than when I had CATS. I don't throw any CELs, but I believe that depends upon your particular ECU. Mine is FVD and all my lights work normally.
With the mufflers bypassed also, it is OBNOXIOUS. I usually only put them on whem I am going to the track, and by the time I get home I am glad to take them off! It IS fun driving through a canyon and hearing the turbos whistle though.

Rob 97 993c2

scott,
i dont get it ... does the muffler bypass allow you to hear the turbos whistle?
im looking for better sound when the car is running harder and love to hear turbos spool and then let-air-out, but, not sound like an airplane when the car is idle.
Do you recommend the cat-bypas?

ScottMellor

Yes I recommend the CAT bypass. With the TechEFX mufflers, which are similar to RSRs, the sound is more aggressive and nice and deep but without any annoying resonance. In my not so humble opinion, compared to a car with CATS and a muffler bypass it is a much nicer sound.
As I say, when I'm CAT bypass + muffler bypass, its fricken loud and the resonance at 2500-3000 makes you want to stab an icepick in your ears on a long trip. (Or drive a lot faster And yes the turbos seem to whistle more noticeably.

ca993twin

I have the stock cats (and stock k-16 turbos) with muffler bypasses. Scott and I have had several opportunities to have our cars side-by-side and compare the sound. When he has his mufflers on, the cars make about the same volume of noise, but his car sounds a bit "beefier" than mine. When he has his mufflers off, its quite a bit louder, but either Scott is a wussie, or my hearing is going south, because I don't think its as obnoxious as he says. My vote is for wussie.

Rassel

I will not put on cat bypass. Two reasons for this:
1.) SBP (Svensk Bilprovning) won't pass the car and I won't be allowed to drive it.
2.) I have factory K24, so the ECU comes from Porsche, and I'll get CEL.

I just want a little performance boost by spinning Turbos earlier, and it should be a modification that I can easily convert back to standard.

ca993twin

Muffler bypasses are inexpensive (but Porsche standards, anyway), perfectly legal, no CEL issues, and take about 10 minutes to install, even for a doofus like me. Plus they save a lot of weight (since the mufflers now get stored in a corner of your garage), and allow a little better cooling flow to the turbos. Its a no-brainer. And, as someone ponted out, they are only really noisey at cold start; they soon quiet to a reasonable level, and actually get quieter as the turbos start spinning.

What are you waiting for?

ScottMellor

Steve:
Turn your hearing aid back on.

Woodster

I PURCHASED USED RACING CATS (HJS), AND PLAN TO USE ROBIN'S RSR MUFFLERS BUT UNFORTUNEATELY I HAVE HAD NO LUCK GETTING ANY RESPONSE FROM HIM. THE WORD IS THAT HE MAKES THE BEST SOUNDING MUFFLER (OPINION). MY BUDDY (PORSCHE CLUB RACER IN MPLS/993TT) HAS HI-FLOW CATS AND MUFFLER BYPASS AND IT IS FRICKEN LOUD!!!

ScottMellor

Marty,
Don't shout, I have a hangover.

Rassel

Ok, then I have only one question that have not been answered yet.
Will by dual-pipes fit on muffler by-pass?
And what brand do I need to get then?

ca993twin

I think the GHL bypasses use your existing tips, whereas the Fabspeed bypasses come with their own tips as one piece. GHL is a sponsor here, I think.

Scott... I flipped the switch for the hearing aid, and my pace-maker started running in overdrive. So I still can't hear, but I don't hear really fast.

nman413

Mmmmm, cat bypasses. Me want.

seege

Hurry Jauder and you can beat me to this one