Archer911

After talking to some knowledgable guys at our local Porsches and Coffee I went ahead and ordered a Euro-PreMuffler Cat Bypass Pipe by Fabspeed.

I believe the cat on my 1987 Carrera is original. With 130k miles I would expect it is restricting flow a bit.

Wondering what issues if any you've had on install and after the fact.

Thanks.

Miguel87911

I have been wanting to do this also. Following post.

grgallo

i had a FVD Brombacher cat bypass installed, no issues but did end up getting a new oxygen sensor, seemed that removing the cat revealed a bad O2 sensor or just random events. all is well and am greatly pleased with the bypass, nicer low end sound and improved throttle response (my opinion), car drive beautifully

Archer911

grgallo, I put in a new sensor a few years back so hopefully won't have an issue. Pelican/Fabspeed do offer "O2 Spacers" to alleviate any error light but I'll wait and see. Should have the install done by the end of next week.

Thanks.

theiceman

Just the bitch of a time getting the old bolts off. If you are lucky they will just snap off and done.

Ryanonarcher

Thinking about doing the same...looking forward to your review

Archer911

I'm going to do video/audio to A/B the difference.

Will also talk about the install.

Archer911

Too lazy and/or busy to do a comparison video. The sound difference is so subtle that I doubt very much it would be noticeable when recorded.

The new development is that water has started dripping from between the original muffler and the mounting bracket. water from an air cooled car.

I believe it is a muffler failure that was probably accelerated by the installation of the bypass pipe (more flow and a wetter stream). So now I need to put on a new muffler. The domino effect.

rusnak

Are you saying that there is a leak between the bypass and the muffler?

Archer911

Not with the car now otherwise I would include a pic. (one from internet shown here)
The leak is almost dead-center from the muffler where it rests against the pipe connecting the exhaust manifolds. I can hear a bit of a blow sound as well.

Jherriott

I have both the fabspeed bypass and supercup exhaust. On my youtube link in the signature there are some vids of different configurations, however the sound capture leaves a little to be desired. As it sits now it's very deep and aggressive sounding at idle, but really has this trumpet like howl after 4,000 rpms. Probably won't be 'til next year before I do a proper recording due to the break-in of the rebuild.

Jase.

Archer911

I will definitely install a new exhaust in a few weeks. I'll stick to single tail pipe as I don't want to modify my original rear valance.

I really want the car to still sound like a 911 so I'll listen to what sound files I can find before ordering.

Adams

I had been very concerned about noise level going too far in my car. Not a fan of loud, but of well tuned performance.

Went very close to your route.

Before: Stock cat, Fabspeed single in, dual out.
After: Euro cat, Dansk single out 'sport' (84mm)

Noise-wise, the car actually got quieter. Not my imagination.

Additional mods at the same time: S-Car 4 hole injectors, Sal's tuned chip.
Really excellent changes all around.

Overall I am very pleased with the exhaust change, and especially the noise and heat reduction.

911GA

I did the cat bypass myself on my 86' 3.2 911. Again not the same set up, but I can offer what I experienced with installation.

Installation was easy. I just cut my old bolts off with an air chisel and replaced them. I cut off the muffler straps with tin snips and had no other issues. If I had to guess it took me an hour at a leisurely pace.

I did a Bursch one in one out exhaust with the cat bypass. It is not loud at all. It made the whirl of the 3.2 have a little bit of more tone. It sounds really good when down shifting which is it's loudest point, however it is not loud. When accelerating it sounds good, but I have not noticed any noise that is unpleasant.

Archer911

Do you mean Sal from Rhode Island? The 4 hole injectors sound like a great idea as well and I know Sal did that to his 911.