[410BN]

I installed VRSF 3" catless downpipes over the weekend (e92 335i). Nice product and great customer service.

Now that they are installed, I'm getting an irritating noise between 1600 RPM and 2000 RPM under load in any gear (video link below). I can't tell if its a rattle or if it's normal rasp (secondary cats are gone too, I still have the stock mufflers).

It sounds like its coming out of the exhaust rather than from under the car but I haven't noticed this sound from other catless N54s. I forced the exhaust flap open with the JB4 and the sound persisted so it's not that. It doesn't make the noise on deceleration, only on acceleration.

What do you guys think? Normal rasp or do I have a rattle?

The passenger side downpipe is sitting very close to the frame but not touching. I'd say it has about an 1/10th inch (or less) clearance.

[e92_enthusiast_1]

I dont have that sound, VRSF catless here too, so it's hard to say what it could be. Almost like if it's barely touching some metal like barely barely rubbing.

I can take some video later if you want.

[410BN]

Do you still have secondary cats installed? I've read that some have experienced a decent amount of rasp when deleting all four cats (especially when retaining stock mufflers) but I'm not sure if this is the same thing. It almost sounds like a civic with a ricer exhaust for that 400-500 rpm range.

[Tiago@VRSF]

Generally most of the time you get a rattle from downpipes is when they are incorrectly installed. The noise you could be hearing is the downpipes making contact with the sub frame. This can be corrected by loosening the DP's, rotating the pipes away from the problem area and tightening the clamps/bolts.

I haven't had to answer one of these questions in a while and we've sold twice as many V2's and the old V1's so I guess we've done something right

[410BN]

Tiago,

Does it sound like a rattle to you in the video? The downpipes themselves fit great before trying to bolt them to the mid pipes. I can't get the mid pipes to move much and it is forcing the passenger side downpipe to sit very close to the sub frame once bolted up to the mid pipes. I actually slid a screw driver in between the subframe and the downpipe while tightening everything up to ensure I had some amount of clearance.

[Tiago@VRSF]

To be honest it sounds more like a leak or rasp, generally rattles near the sub frame are only present when you're taking a turn, not when accelerating at high load.

If there's a clearance issue you can usually bend the heatshield in a bit or use the mid pipe hanger's lateral adjustment to move the mid-pipe away from the passenger side. It's generally easier to move the passenger side short pipe over towards the long pipe, clamp down the v-band and then bolt up the mid pipe to ensure it doesn't head towards the subframe. You only need a 3-4mm of clearance in order to prevent contact.

[Cloud9blue]

Yep, wastegate rattle right there. I have the exact same sound during low rpm acceleration (although not as loud), had it since JB4. Fully catless exhaust just make it louder.

Typically when people reports rattle in deceleration, it is due to the wastegate actuator arm and pivot wearing out. When it is acceleration, it is due to the flapper valve tapping against the turbo housing when the wastegate is partially shut for low-medium boost. Some flappers are just looser than the other and typically a tune brings the wastegate valve closer for better boost response, so you gonna hear more of it with dp and JB4. I tried tuning it out with JB4, but I either have to suffer extreme turbo lag (too open) or boost surge (too closed). oh well... Give menu 10 and 12 some fiddling to see if you can tune the noise down a bit without suffering much performance.

No harm and perfectly normal if your boost and engine response is fine. I just learnt to live it after a few days.

[SaviorXi]

Originally Posted by 410BN

I installed VRSF 3" catless downpipes over the weekend (e92 335i). Nice product and great customer service.

Now that they are installed, I'm getting an irritating noise between 1600 RPM and 2000 RPM under load in any gear (video link below). I can't tell if its a rattle or if it's normal rasp (secondary cats are gone too, I still have the stock mufflers).

It sounds like its coming out of the exhaust rather than from under the car but I haven't noticed this sound from other catless N54s. I forced the exhaust flap open with the JB4 and the sound persisted so it's not that. It doesn't make the noise on deceleration, only on acceleration.

What do you guys think? Normal rasp or do I have a rattle?

The passenger side downpipe is sitting very close to the frame but not touching. I'd say it has about an 1/10th inch (or less) clearance.

Check out my thread. I had the exact same problem when I installed my VRSF downpipes. (only difference was I also deleted my secondary cats) The sound I had was identical to you and the RPMs were also the same. Listen to the many clips on the below thread. It was not metal from an improper install. It was not wastegate rattle. It WAS rasp. 2 Vibrant resonators and the problem was solved for good.

http://www.e90post.com/forums/showthread.php?t=859071

[410BN]

Originally Posted by Cloud9blue

Yep, wastegate rattle right there. I have the exact same sound during low rpm acceleration (although not as loud), had it since JB4. Fully catless exhaust just make it louder.

Typically when people reports rattle in deceleration, it is due to the wastegate actuator arm and pivot wearing out. When it is acceleration, it is due to the flapper valve tapping against the turbo housing when the wastegate is partially shut for low-medium boost. Some flappers are just looser than the other and typically a tune brings the wastegate valve closer for better boost response, so you gonna hear more of it with dp and JB4. I tried tuning it out with JB4, but I either have to suffer extreme turbo lag (too open) or boost surge (too closed). oh well... Give menu 10 and 12 some fiddling to see if you can tune the noise down a bit without suffering much performance.

No harm and perfectly normal if your boost and engine response is fine. I just learnt to live it after a few days.

Unfortunately I've been playing around with option 10 and option 12 and it hasn't made a difference. I tried option 10 set at 800rpm, 2500 rpm, 4000 rpm, and 4500 rpm. I also tried various settings for option 12. I even popped off the vacuum lines from the vacuum canisters to theoretically keep the wastegate positions stationary and the rattle/rasp was still present. If it was the wastegates, I feel that the noise should have stopped after removing the vacuum source from the wastgate actuators. Am I thinking about this correctly?

By the way, I have RB turbos that have probably 10k miles or so on them.

Originally Posted by SaviorXi

Check out my thread. I had the exact same problem when I installed my VRSF downpipes. (only difference was I also deleted my secondary cats) The sound I had was identical to you and the RPMs were also the same. Listen to the many clips on the below thread. It was not metal from an improper install. It was not wastegate rattle. It WAS rasp. 2 Vibrant resonators and the problem was solved for good.

http://www.e90post.com/forums/showthread.php?t=859071

I was actually checking out your thread a bit earlier and that's what made me think it COULD just be rasp. My secondary cats are deleted as well.

[SaviorXi]

Originally Posted by 410BN

Unfortunately I've been playing around with option 10 and option 12 and it hasn't made a difference. I tried option 10 set at 800rpm, 2500 rpm, 4000 rpm, and 4500 rpm. I also tried various settings for option 12. I even popped off the vacuum lines from the vacuum canisters to theoretically keep the wastegate positions stationary and rattle/rasp remained. If it was the wastegates, I feel that the noise should have stopped after removing the vacuum source from the wastgate actuators. Am I thinking about this correctly?

By the way, I have RB turbos that have probably 10k miles or so on them.



I was actually checking out your thread a bit earlier and that's what made me think it COULD just be rasp. My secondary cats are deleted as well.

I guarantee if you get the 2 vibrant resonators welded in you will no longer have that rattle/ rasp

[Tiago@VRSF]

I didn't realize you didn't have your rear cats in, it's most likely rasp, especially in that RPM range.

[410BN]

Originally Posted by SaviorXi

I guarantee if you get the 2 vibrant resonators welded in you will no longer have that rattle/ rasp

After watching the 3rd and 4th videos you posted in your thread, my car does sound IDENTICAL to yours. Do you happen to know the part number to the vibrant resonators you used?

I also have magnaflow mufflers sitting in the shed that I'm about to put on. I wonder if going from stock mufflers to magnaflow mufflers would eliminate it or if I'd still need to install some resonators.

[410BN]

Originally Posted by Tiago@VRSF

I didn't realize you didn't have your rear cats in, it's most likely rasp, especially in that RPM range.

Thanks Tiago. By the way, the intercooler and the downpipes turned my car into a whole new beast

[Cloud9blue]

Originally Posted by 410BN

Unfortunately I've been playing around with option 10 and option 12 and it hasn't made a difference. I tried option 10 set at 800rpm, 2500 rpm, 4000 rpm, and 4500 rpm. I also tried various settings for option 12. I even popped off the vacuum lines from the vacuum canisters to theoretically keep the wastegate positions stationary and the rattle/rasp was still present. If it was the wastegates, I feel that the noise should have stopped after removing the vacuum source from the wastgate actuators. Am I thinking about this correctly?

By the way, I have RB turbos that have probably 10k miles or so on them.



I was actually checking out your thread a bit earlier and that's what made me think it COULD just be rasp. My secondary cats are deleted as well.

Hummm, guess it is rasp then if that's the case. Mine is completely rasp free with VRSF dp, but I have AE exhaust.

[SaviorXi]

Originally Posted by 410BN

After watching the 3rd and 4th videos you posted in your thread, my car does sound IDENTICAL to yours. Do you happen to know the part number to the vibrant resonators you used?

I also have magnaflow mufflers sitting in the shed that I'm about to put on. I wonder if going from stock mufflers to magnaflow mufflers would eliminate it or if I'd still need to install some resonators.

You are still going to need the resonators I believe.

I purchased 2 Vibrant 1792 Bottle Style Resonator

Here is the link to the ones I purchased. You need 2.

http://www.amazon.com/gp/product/B00...?ie=UTF8&psc=1

I now think I may add some high flow cats to my setup. I am tired of the smell and it is a little loud with my BMW performance exhaust and no secondaries. I'm thinking the Vibrant 1792's, high flow secondary cats, VRSF downpipes and my BMW performance exhaust may be the magic combination I have been searching for. We will see.

[chepy24]

another vote for rasp... i did muffler delete and secondary delete and got the same noise

[410BN]

Thanks for the input everyone. It looks like I'll be picking up some resonators shortly.

[bfoolish1339]

Originally Posted by 410BN

Thanks for the input everyone. It looks like I'll be picking up some resonators shortly.

I had a vibration/gurgle at low speeds when I turned the wheel all the way right it left. Turns our it was touching the subframe. Easy fix by who ever installed it.

[lomon98]

Hello,

Just installed the vrsf catless dp + some welded single walled 3.5" tips on my 12' 335i e92. Just wanted to get some feedback on the sound I get, does this sound like wastegate rattle?

1. Exhaust soundCold start + warmed up
2. Engine sound

I notice a short of "metallic" sound when cruising at low speeds, that was the sound which brought me to this thread actually. Can get a sound clip of it next week if needed.

Any feedback is very welcome! Cheers!