Fabspeed Mufflers and Resonance

So now that Fabspeed made good to Manny, what is up with this resonance thing at 2000 rpm? I thought I wanted these mufflers, but I don't think I do if this is the case. Do other brands have problems with resonance?

None with PSE!

Having had fabspeed and changed to PSE I can only concur with Dell.

When most folks install PSE, do they install the switch or just the mufflers and leave it in loud mode?

I'm full on baby! You can install the switch and vacuum lines but why? Some like to be able to turn "off" the PSE.

It's like having one of those old "Turbo" buttons on old computers. All it really does is slow down the computer.

installing the switch was a hell of a lot more labour, so i went without. It was great Just waiting for PSE for my cayman now...

+1 for PSE

Go PSE!! Sounds great, no resonance (tastes great, less filling)!! I have the full switch operation installed on mine. It's nice to be able to tone it down occasionally.

No resonance with the fabs, just a nice, smooth, gritty sound. All these PSE guys are snobs...

+1

On a different thread I started a discussion with the provocative argument that PSE adds weight and decreases hp of the n/a 996. Dell replied: "FYI....PSE does NOT decrease hp. Not sure where you heard that from." ... and I quoted following: "There's a discussion on German P Car boards like "elfertreff.de" (you may say Germans have no clue about Porsche) that talks about following issue: opening the valve in the muffler changes the length of the exhaust pipe and the exhaust back pressure to the engine. The engines are setup to operate optimal under a certain back pressure and if you don't change the settings on the ECU, there's a loss of hp and torque. Porsche doesn't claim any hp gain but they do also not confirm that the PSE keeps the car on stock hp with the open valve. Have you done a before - after dyno? There's a report of a German 996 owner that said his car had a 6kmh lower top speed with the open valve than with the closed valve. Above is just a discussion input as not scientifically proven, so please prove me wrong." Can anyone comment on this?

+3 I love my fabspeeds. The scary thing is there are times I wish it was a bit louder. Pete

I love my Fabspeeds.

+1 for Poor-Man's PSE (modded-OEM cans) hee hee

+2

I couldn't comment on the rest of the assertions, but this one is suspect to me. I'd have to wonder about how controlled his top speed tests were. Generally, the only time a less restrictive exhaust does anything meaningful is at the top end. All else being equal, an open tube (of the same diameter, of course) should have given him more top end, even if at the cost of low end torque. It's just physics. FWIW, to the original poster, I don't have any resonance problems either. I use the EVOMS exhaust, not a popular choice on this forum, but I'm happy with it. At the 2,000 rpms that the Fabspeed problem was alleged to occur at, mine is dead quiet. Mind you, 2,000 rpm is pretty much just for parking lots, in my experience. YMMV and all that...

I had a 2001 cab with a set of B&B which never suffered from resonance even in the lower rpm range. I have now a set of Tubi which I can not detect resonane either. I have, however, many friends with Fabspeed and they do not complain. I think this topic is also very subjective, what might be annoying to someone might not be to others.

Like I've said before, when it comes to mods on this board it's all ancedotal because none dyno.

I have Fabspeeds on my car and the only resonation is accelerating slowly at lower speeds. Absolutely no resonation at cruise at any speed or rpms. Keep in mind that the PSE is performance sound only, while you will gain a power improvement with the Fabspeed exhaust.

"I have Fabspeeds on my car and the only resonation is accelerating slowly at lower speeds. Absolutely no resonation at cruise at any speed or rpms. Keep in mind that the PSE is performance sound only, while you will gain a power improvement with the Fabspeed exhaust." I have no experience with the Fabspeed exhaust. When you say there is a gain in power (hp/torque), does this gain encompss the entire RPM range? In particular, is there any specific RPM range that you might actually lose power, while you gain some at high RPM?

+3 on the Poor -Man's PSE , especially since I have a daughter that is a Freshman in college!

Mine is one year ahead. She is spending more on her spring break Mexico trip than I think I spent on my entire college tuition. Perhaps the poor man's route is the way to go.

[Image-only post; no author-written text. Original image references:] https://rennlist.com/forums/images/smilies/eek.gif https://rennlist.com/forums/images/smilies/beerchug.gif

I never dynoed my Fabspeed seperately, but in combination a K&N 63 series intake I increased from a peak of 270.1 to 292.1 hp on a dynoject 248C. They made 15 rwhp at 4400 rpms and almost 30 rwhp at the redline. My peak HP increased from at 6200 rpms stock to 6600 rpms with the 2 mods. The other advantage to the Fabspeed or most aftermarket exhausts over the PSE is the weight reduction, which is about 30 lbs. The PSE is heaviest (actually heavier than the base exhaust) you can put on a 996.

I hear ya!

+ 1 Defiantly a lot lighter. I have them on and don't have a problem. I do like the sound of PSE but i'd rather spend less and weight less.

Thanks for your post carrera02. I do also have the K&N63 CAI and I hesitate to go with the PSE because of its weight. Just to make the car louder is not enough for an exhaust, at least for me but I'm also skeptical with aftermarket promises in terms of hp gains. I doubt that my CAI really increased the performance of my car, definitely not by >20hp.

Anyone care to elaborate on the specifics of the poor man's mods to the stock OEM exhaust?

I think this thread will answer most, if not all, of your questions. If not, there are other PSE mod threads that have even more info. Hope this helps! https://rennlist.com/forums/996-forum/304600-pse-modded-3-6-mufflers-how-close-in-sound-to-a-real-pse.html

Doesn't the standard exhaust on a 996 have a modest amount of resonance around 2k rpm? I'm wondering if the Fabspeeds just accentuate this to some degree, which would account for why some people say there's no more resonance than normal, and some people detect the resonance more fully.

My car came with the Fabspeed set up. There clearly is resonance at 2K. But seriously stop and ask yourself when do you (or should you) lug the engine at 2K rpm? After I got used to my car I find that I am never driving around at 2k and when I am the resonance is a quick reminder to me of hey stupid downshift already this isn't a truck !

There are a lot of "+1's" on this thread...so here is another one +1

I agree, weight and cost were what I used in making my decision........ who drives their car at 2000 RPM anyway? I don't........

One more thing... buy an exhaust for how it sounds because in the end almost all of them offer negligible performance improvements over stock. The majority of them if you look at their dyno sheets increase the hp slightly across the curve but very minor overall peak gains. <flame suit on>

Have to chime in - I don't think 2k is lugging it. Sure, you're not really in the powerband, but at the same time, I think the manual says 1500 is where you really need to start worrying about it, and that seemed more reasonable to me. I was happy to keep it at 2k when cruising..

Like I said before ff you are stuck in traffic for a long time, you are going to be in the low rpm range for some time. I agree with justinmm2 that cruising at 2k rpm is a comfortable speed, and if your car suffered from resonance like mine did, you would change the mufflers in a heart beat.

To test the flame retardent suit, what do you consider negligable? I increased 22 RWHP (peak to peak) on the dyno from a Fabspeed exhaust and a K&N intake. I gained 14 rwhp at 4400 rpms and 30 rwhp at redline. That is 8% peak over stock. Saying that is negligable is the same as saying the increase for an X51 option is negligable.

I find this exhaust topic quite interesting. Maybe its because my car is all stock, but she sounds like a old VW Beetle when I start her. I obviously need some serious exhaust work

Or maybe just a new exhaust....

That's the same thought I had when I first started my 996.

I was always embarrassed by that sound.

Dealer just quoted me $4-5k for PSE Sounds a bit aggressive - no?

At most the dealer should be at $2500 on the high side. The cans are $1500 and the install (if you want the dash switch) is another 7-8 hours. Only the cans? 1 hours MAX!

Have to reiterate what Dell says. $4-5k? Insane. The part is $1800-1900 these days, though you might be able to find it for significantly less if you have a nice dealer or don't mind waiting and keeping your eyes peeled. Even 7-8 hours labor, if that's what the book says, is a bit much..

Any dealer will likely match the price that you can get from Sunset and then install it for you. Just negotiate a bit and see what they'll offer. As the guys mentioned above, 4-5k is absurd.

I did the PSE install on my car myself. The cans took a little longer than 1 hr. as I did not have a lift and had some frozen bolts, but with a lift and air tools 1 hr. should be more than enough. The wiring only took about 3-4 hrs. in the driveway.