Noise Related To New Split Dump Pipe...

[petgts4]

I tried searching but had no luck!

I just installed a stainless steel split dump pipe onto my r32 (rb25 turbo), and immediately i noticed a strange noise that occurs only between around 2000-4000rpm... It sounds like the noise you make when you blow on the top of a bottle, but really loud!

It's as if the air inside the dump pipe is resonating when a certain amount of exhaust gas flow through it.

Anyone else had this happen after swapping their dump pipe for an aftermarket one?

Cheers!

[RANDY]

I hear something like that with the stocker actually... Not all the time, it's weird.

[Cillham]

Any performace loss/increase over existing dump/front pipe?

[mad082]

was it a cheaper dump pipe (like off ebay)? it may be that the wastegate pipe isn't properly lined up with the hole, so it has a flap in there that is altering the airflow. mine had this, but i just took to it with a diegrinder.

[EvilINGT]

I get a similar sound, sort of like alternator whine, but it doesnt come through the speakers, funny. BATMBLS spilt dump, i dont care though as usually the stereo is right up and i cant hear it .

cheers

Evil

[Liz]

was it a cheaper dump pipe (like off ebay)? it may be that the wastegate pipe isn't properly lined up with the hole, so it has a flap in there that is altering the airflow. mine had this, but i just took to it with a diegrinder.

yes, that sounds likely.

just take it off and have a look at the piping, could be as simple as the welds not being ground back.

[mad082]

i get that high pitched whine through the speakers too. if i turn the stereo off it goes away.

[maccattack]

Stainless dumps are made of thinner material than the standard cast dumps. They do tend to resonate more, not only because of the airflow but sound from the engine. You will always get a change in engine note with stainless dumps.

[petgts4]

I took a look at the inside of the dump pipe, and it does have a bit of a metal flap at the wastegate return section that could be causing the noise. Thanks mad082, i'll get my diegrinder out and hopefully that will sort it out!

Cillham, i did notice that full boost is reached a bit quicker which is probably due to the gases flowing out more freely, so if anything, it's an improvement.

Thanks for the replies guys!

Edited August 24, 2006 by petgts4