Mk6 GTI louder with APR downpipe installed (already had a resonated catback exhaust)

[MrGTIandRfan]

I had a aftermarket catback exhaust with a resonator prior to getting the APR downpipe fitted.

I've noticed that the car now sounds meatier, but louder and droney as well - the drone is almost as bad as it was prior to having a resonator fitted originally. I knew that the sound would change somewhat, but not for it to be much louder.

Could it be that they have removed the resonator upon installing the downpipe?

What are my options for quietening the sound down?

[Corey_R]

Hi. Welcome to the forums.

The downpipe will increase the flow of air significantly, because it's better designed and larger than stock, but also because it changes to a hi-flow cat and moves the cat further away from the turbo.

The DP's pipe attaches to the cat-back before the central resonator, see this diagram:


You really should have got the DP installed before getting an aftermarket cat-back, especially if it was custom made.

I'm not sure really what your options for quietening it down are now. In no particular order.
Remove the aftermarket air intake (if you have one).
Try putting the stock cat-back on.
Redesign/rebuild the aftermarket cat-back to be quieter.
Remove the DP and go back to stock.
etc

[MrGTIandRfan]

How can I get the catback redesigned to be quieter/less droney?

The workshop never contacted me prior to fitting the downpipe, so I really had no input into what my options were. Additionally, I purchased the car with the catback exhaust already fitted.

Don't get me wrong, it's not as bad as those Jap-ricer cars; but a bit out of place for a nice euro hatchback.

Besides that, the car is fantastic to drive.

[Corey_R]

You'd need to take the car to a local exhaust shop and discuss your options.
Did the person you bought the car from also give you the stock cat-back? I find that most cat-backs, even if they're resonated, are louder and dronier than the stock exhaust... especially once you have the DP.

[aVex]

How can I get the catback redesigned to be quieter/less droney?

Swap your catback to the stock one, I don't mind swapping my stock catback with your APR cat back of course with some monetary compensation. We can meet half way in Warrnambool or something :p

[Corey_R]

The OP didn't say he has an APR cat back. Being that the MK6 APR cat-back is an RSC and they have zero drone with either the stock or APR DP, I doubt it would be. The RSC catback is loud at WOT, but no drone.

[MrGTIandRfan]

I don't have the RSC, no.

I gave it a bit of a better drive today.

The DSG 'fart' that occurs when you upshift gears sounds really different shifting from first to second under heavy throttle. The exhaust note under heavy throttle definitely doesn't sound as good - especially with the dreaded wastegate rattle now being emphasised more than before. At idle, the exhaust sounds like those old cars with mufflers falling apart.

I didn't think just changing the downpipe would have such a dramatic effect on the exhaust note. It sounded great before, but now I am a bit embarrassed to open up the throttle due to the noise.

NOT HAPPY.

[walbjj]

thats one reason why u dont get custom exhausts, although in ur case, u had no choice as it was on the car. didnt the seller have the original?
its also one reason why im keeping my catback stock and changing the downpipe only. getting too old for all that noise

[MrGTIandRfan]

thats one reason why u dont get custom exhausts, although in ur case, u had no choice as it was on the car. didnt the seller have the original?
its also one reason why im keeping my catback stock and changing the downpipe only. getting too old for all that noise

The original is at the exhaust shop where the catback was installed - I just need to pick it up.

The custom catback that was installed sounded pretty good prior to the downpipe install - not loud but great under throttle. Now it just barks, and sounds crap when the famous EA888 wastegate rattle sound appears - it's random.

[Corey_R]

Well that's what I'm saying... the custom exhaust has been made with the stock DP and cat in place, and it's been tuned to that extent. Now it sounds crap because it wasn't designed to be used with a performance downpipe / cat. It's not the DP's fault, it's the cat's. Put the stock cat-back on and see how you go