SCGuy

Question for the forum...I just installed the Sharkwerks center exhaust on my 997.2. The exhaust didn't fit perfectly (looks like one of the flanges had rotated slightly during the welding process), and thus I had to slightly elongate a couple of the holes on one of the flanges with a file and then tap the exhaust into place. It then bolted on fine; everything else lined up and I've confirmed that everything is tight.

However, at idle, I now have a slight vibration that I can feel in the drivers seat and see in the side mirror. The vibration goes away as soon as I add 100-200 RPM, but it is there at idle. I've looked at the exhaust while idling, but it is not vibrating (heck, I can even read the logo on the exhaust with no issues). The side mufflers are vibrating, but not the center pipes. There is also lots of clearance, and I can't see anything loose or hitting the exhaust.

I haven't driven a lot yet...just 60 miles or so.

Has anyone else experienced this? I'm talking to the guys at Sharkwerks, but wanted to check with everyone here as well. Any suggestions? Just a byproduct of the different exhaust gas flow? Or issues with the exhaust system now under slight tension?

rijowysock

i have same problem with my fabspeed center replacement piece...

i was thinking about it and the oem piece is "solid" as well.. so this cant be the problem, i think its where it mounts to the car, maybe more rigid now than before.. i bought some rubber spacers and was going to put them where the exhaust mounts to the car... but i think they are too thin... so i was going to buy a hanger strap, cut it and use that instead..

havent had time tho.

RonCT

Same thing here and it's a slightly lower idle speed probably due to the ECU adjusting to the new set of inputs / outputs. My vibration was such that the passenger seat rattled slightly. What cured it was when the ECU reset after my battery drew down (note to self: Do not leave the key in the ignition overnight). I believe I posted this here at the forum and other suggested to just disconnect the battery for a couple of hours, which also resets the ECU. I'm sure Alex will chime in here. Once I jumped the car and drove off, I realized the ECU reset solved the low / rough idle situation.

Edgy01

I'm sure all those aftermarket guys will take back these pieces and reinstall them for you so that it is perfect.

rijowysock

:-(. Was just sitting at light and passenger asked me why so shaky

rijowysock

Idle is at 700. Rpm btw at 93 outside. Oil at 200. Coolant at 175

RonCT

Tell your passenger it's a Sports Car not an electric Prius

cole328

I think a slight shake at a light is intimidating to other cars......I'd leave it alone

MrMetrx

f4 plt

I have had my Sharkwerks center muffler by pass pipe on for almost 8 months and 7000+ miles and have not noticed a vibration, decrease in idle speed or any of the issues mentioned. I just enjoy the sound on acceleration the reduction of heat and weight and the slight increase in Hp. Guess I'm a rare but happy camper.

Seriously, my 997.2 C2S was a late November production, has PDK and when the dealer did an update on both the transmission and engine management software about 45 days ago an already smooth engine became smoother and the PDK which shifted great got better. Might want to check if your car needs the software upload.

rijowysock

i will call porsche tomorrow regarding updates... my idle i listed above, so im not sure if thats low/high but the vibration is bad... causes rattles from what seems like every panel and the steering..

never had it prior to the new center pipe..

if no updates, i will invest some time into some make shift dampers where the center mounts to the car.

SCGuy

My idle is around the same...perhaps around 650 rpm. Taking it to 800 rpm eliminates the vibration. No PDK here, so that update won't help...but keep us posted as to whether there is a different update that needs to be applied to the engine. Would love to figure this one out!

JohnAMG

I installed mine last weekend and it had a very subtle vibration during idling also. I just tweak it a bit tonight and it seems to get rid of the vibration. What I did was at the connectors between the bypass pipe and the side muffler pipe, I made sure the sleeve were evenly divided between the 2 pipes and tight the nuts simultaneously. Also the bracket that hold the pipe to the chassis, I made sure I didn't over tighten it. I hope it works out for you.

John

rijowysock

i will teak those bolts/clamps tomorrow.. tonight i loosened a few here/there to see what was going on and didnt get anywhere... so it sounds like they built each part to take a little bit of the grunt.. and we just over tightened it all.

sharkster

Hi SCGuy, definately check the side mufflers again and just make sure nothing has come loose or needs to be tightened again. I didn't notice anything like that on ours or the ones we've done locally although some folks have said that there needs to be an ECU update (more so with the PDK cars so that's not you etc...) and let us know. Installed a few more from that same batch with no issues so if you like I can send you out another one so that you don't need to notch it etc... Just let me know.

There's a change in back pressure there for sure that was/is a good idea... Once the ECU re-adjusts etc... that could make some sense...

There was a customer's car that we were going to do a full tubi system on a couple of weeks ago and before coming in he'd developed a rattle etc.... And this was the issue:
http://videos.g33kd.net/997%202%2010...er%20Clamp.pdf