Fabspeed Bypass Pipes Installed on my GTS - Before & After Video
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Fabspeed Bypass Pipes Installed on my GTS - Before & After Video
I had Fabspeed Bypass Pipes installed on my '09 GTS last weekend.
Overall I'm happy with the results, but I have a couple of issues:
1. On a cold start, they sound like they are rattling for about 3-5 seconds. I verified that the pipes are NOT hitting the transmission cross brace, and they are not hitting anything on the under-carriage of the car. I believe it's pure resonance that I hear coming through the pipes as the warm air from the manifold passes through the cold pipes. It's a very loud and bad sound that I hope goes away over time. Anyone else experiencing this?
2. The pipes sound equally loud in Normal and Sport modes under full hard acceleration. In sport mode, it might be marginally louder....perhaps 5-10% but I'm surprised at how loud they are in normal mode. Not necessarily a bad thing, but something that is noticeable. When cruising with a light throttle there is a big difference in sound pressure levels (SPLs) between normal and sport....as it should be.
3. The sound coming through the pipes is very apparent, and comes on VERY quickly when reaching a specific RPM. I believe it's at around 2,800RPM. It sounds as if a valve opens to really create the higher SPLs. I wish the increase in sound with the throttle was a little more gradual and not so abrupt. It sounds like a switch is being turned on and off. Again, anyone else experiencing this?
Below is my video of the before and after with sport mode turned on and off. I apologize for the poor audio quality coming from my point & shoot camera. I appreciate your feedback.
pardon my ignorance , but i didn't know that there would be a difference in engine sounds when switching modes. i thought it was mainly the suspension and shifting charachteristics that changed?
Rattle sound on cold start is normal... Mine does the same thing and it does not go away. I have had the pipes for some time now. The rattle should only last a few moments while the engine warms. If you shift it into reverse it stops right away.
I have to say I am not happy at all with the rattling sound of the pipes on a cold start. I live in a condo with a common parking garage, and it's embarassing to say the least when someone sees such a nice SUV start up and make a sound like something is wrong with the vehicle.
I've heard others complain about the rattlng noise, but I'm unaware if the problem was ever rectified or has gone away.
I find it hard to believe that this noise is considered normal. What is Fabspeeds recommendation on how to fix this problem?
Quote:
Originally Posted by caltex
Rattle sound on cold start is normal... Mine does the same thing and it does not go away. I have had the pipes for some time now. The rattle should only last a few moments while the engine warms. If you shift it into reverse it stops right away.
Rattle sound on cold start is normal... Mine does the same thing and it does not go away. I have had the pipes for some time now. The rattle should only last a few moments while the engine warms. If you shift it into reverse it stops right away.
I hate that! 
Linear Mode
