How many have cat bypass and muffler bypass together?

[oregonmon]

Just watched the demo on Fabspeed site and they have cat bypass $300 and muffler bypass $60 combo that sounds great but you know you can't tell how loud it is. Also curious about Bursch bypass products. I listened to all the past posts but didn't see a lot of these. Vids or clips would be excellent.

[old man neri]

I actually would like to know this as well.

[porsche930dude]

Just take your muffler off and youll get a good idea of its loudness. Just dont drive it for too long or youll scorch the bottom of your bumper pad. ask me how i know

[lfot]

Member glewis80SC has that setup on his car. I've heard it at the track and it sounds good, but it is pretty loud. By comparison though, I don't think it's any louder than my bursch bypass w/ M&K 1in/1out.

LOUD

[ninesixfour]

A friend ran the Fabspeed muffler bypass with a cat bypass for a while last year and it is seriously LOUD!! I'm talking open pipes, embarrassed to pull out of your driveway, that video doesn't do it justice LOUD, I need earplugs LOUD!! Did I say LOUD? Track-only for sure and even then it was one of the loudest cars there.
Here's in car video of that exhaust. Again, this video does not properly demonstrate how loud this is. I'm driving the white SC in front of him with my muffler bypass in place and you can barely hear my car.
The "exhaust sounds" video in my signature is my car with the stock heat exchangers, stock cat, and the Fabspeed muffler bypass. It's still a lot louder than stock but not nearly as nasty as the cat bypass/muffler bypass combo. FWIW my friend mentioned above reinstalled his cat after hearing my car and is much happier with it.
Also, according to the exhaust experts here on Pelican, the double bypass exhaust probably produces less power than stock. You don't want to completely eliminate back pressure.

[old man neri]

Originally Posted by lfot

Member glewis80SC has that setup on his car. I've heard it at the track and it sounds good, but it is pretty loud. By comparison though, I don't think it's any louder than my bursch bypass w/ M&K 1in/1out.

LOUD

Too loud for street/city/highway use?

Currently my CAT is welded to my muffler. So if I wanted to get a cat bypass I would need a new muffler or a muffler by pass as well, that is why I was asking.

[lfot]

Originally Posted by old man neri

Too loud for street/city/highway use?

Currently my CAT is welded to my muffler. So if I wanted to get a cat bypass I would need a new muffler or a muffler by pass as well, that is why I was asking.

For street use you should really get a muffler. If you like streetable loud, the m&k's are awesome. They aren't bad with the stock cat, but when I did the bypass it's something you have to be careful about. Like when you pass by cops, upshift to keep the revs down.

Upon second thought, the muffler bypass IS louder than my setup with the m&k. Have to agree with the previous post though, dual bypass will probably get you stopped.

[oregonmon]

Thanks guys for the comments. My next thought is a cat bypass with a Dynomax muffler. Have heard some clips and they sound pretty good. I don't think that would be too loud for a street/autocross car. I'm willing to try this set up for the price because I can't justify $2000 for new SSI's and big name mufller right now. Seems crazy.

[lfot]

Originally Posted by oregonmon

Thanks guys for the comments. My next thought is a cat bypass with a Dynomax muffler. Have heard some clips and they sound pretty good. I don't think that would be too loud for a street/autocross car. I'm willing to try this set up for the price because I can't justify $2000 for new SSI's and big name mufller right now. Seems crazy.

I've heard good things about the Dynomax mufflers, and they're pretty cheap by comparison. I don't know about smog regs where you live, but you'll probably want to hold on to your cat/muffler eternal combo.

[oregonmon]

Well I'm in Oregon. Is there a age/year cut off for not having to pass smog tests?

[lfot]

Originally Posted by oregonmon

Well I'm in Oregon. Is there a age/year cut off for not having to pass smog tests?

Call your local DMV. In California the cutoff is 1975. Anything after that and it still needs to be smogged. Oregon most likely isn't as strict as CA, but I would definitely check with the Oregon DMV to be sure of the laws.

[criv911]

I just installed a muffler bypass on my stock cat. It certainly is loud, but no louder than a Harley. I don't know how much louder a cat bypass would make it. I also found that the cat without the tail pipe that makes the bypass was louder. I probably won't keep it, but it sure is cheap fun.

[polizei]

I actually just sold my Fabspeed muffler and cat bypass on Pelican. criv911 got the muffler bypass With the combo, it sounds like a loud muscle car, yet distinct, up until 4500 RPM or so. Once you get there, it just sounds like a race car. I don't know how else to put it. When you get to that level, you can hear it from a mile away - literally.

I would say if you're considering getting them, go for it. They sell like hot cakes in the used parts forum, and it probably won't cost you much more than 10% of your original investment. AND it's great fun - especially through any underpass

[dw1]

I'm running the Fabspeed premuffler & Dansk 1-in-2-out on my '87 and it sound good - lower in pitch and not that loud.

Mschuep has the same premuffler with a straight pipe. It sounds great, and is not too loud at idle, but you better live in an area very tolerant of loud vehicles to run this setup.

[steve1rob2]

I put the fabspeed cat and muffler bypass on this weekend and I had read this before hand and was very concerned that it would be too loud even though I also own a Harley and am pretty use to the noise. I think it sounds great! I have let 3 other 911 owners in my area listen to it and drive it and all agree with my assessment. The car itself used to get lots of looks, now everyone looks.

It is definately louder than normal, but I had the family with me Sunday and we could easily carry on a conversation. No way would I get stopped in Florida for being too loud. I definately agree with Andy above. It does sound alot like a muscle car at low RPM and a race car at about 4000-4500 RPM.

I am going to get it dyno'ed in a couple weeks, so I will be able to see if it lacks any power, but it sure does not feel like it. It actually feels like it increased HP, but it may be in my head.

It may get old, but for now, I am keeping it. And 2 of the 3 others who test drove it are ordering the same setup.

[SCWDP911]

oregonman, if you want something that loud, check out my videoclips here. My sons love it, but too loud for me for everyday driving. MIght be your cup of tea though. I am still searching for my elusive sound... This ready to bolt on muffler combo is for sale...

[old man neri]

Originally Posted by steve1rob2

I put the fabspeed cat and muffler bypass on this weekend and I had read this before hand and was very concerned that it would be too loud even though I also own a Harley and am pretty use to the noise. I think it sounds great! I have let 3 other 911 owners in my area listen to it and drive it and all agree with my assessment. The car itself used to get lots of looks, now everyone looks.

It is definately louder than normal, but I had the family with me Sunday and we could easily carry on a conversation. No way would I get stopped in Florida for being too loud. I definately agree with Andy above. It does sound alot like a muscle car at low RPM and a race car at about 4000-4500 RPM.

I am going to get it dyno'ed in a couple weeks, so I will be able to see if it lacks any power, but it sure does not feel like it. It actually feels like it increased HP, but it may be in my head.

It may get old, but for now, I am keeping it. And 2 of the 3 others who test drove it are ordering the same setup.

It's comments like this that have me curious, I have a bypass on the way and I was planning on putting a 1 in 1 out dynomax to it. I have a feeling for the small price of the muffler bypass I might give it a shot just for fun.



v8_ranch, that first vid sound amazing.

[grobious911]

I live in Eugene OR, and there are no smog tests period. I have the muffler bypass and the stock cat on my 79 sc.I would'nt want it any louder than it is its pretty darn loud, but it sounds perfect to me.

[oregonmon]

Grobius911, how long have you had that setup and also do you have any clips of it so we can hear?

[EarlyPorsche]

Well you could just leave the cat on and remove the muffler. That way you are not polluting but also have the extra sound you want. No reason to go reverse and leave on the muffler but not the cat.