For all of those who are suffering from wastegate rattle, the solution is here

[Used2be]

Originally Posted by allmotor_2000

Guys - at idle, the wastegate is 'open' meaning exhaust is bypassed from the turbine into the exhaust housing and downpipe. The s63tu does something interesting in the Sport Plus mode where it keeps the wastage semi-closed to help build boost quicker. If that's what the software is doing, then you can just do that by keeping the car in Sport Plus mode.

This makes perfect sense and I don't know why the various commercial tuners on here don't explain how software accomplishes a mechanical fix to the rattle? I have no expertise on turbos, so my questions come from ignorance, but if the rattle is somehow exacerbated when the catalysts are removed from the DPs, is there some inherent sloppiness in the linkage used to open and close the waste gate? Is there back pressure from the restriction of the catalysts which eliminates the rattle on an unmodified engine? That must be a very hot location, so perhaps sloppiness is required to avoid any linkage malfunction? Could the turbos themselves be designed to eliminate the rattle? Does anyone have a connection at Garrett?

[allmotor_2000]

The factory DP's are dual-walled and just muffle the rattle. There is no magic here

[m5james]

Stock downpipes have about 4" of wafer, 1/2" gap and then another layer of wafer. I'm not sure if that big open chamber is good or bad for airflow, but I'll replace them with full 3" once prices become reasonable.

[NightM]

Originally Posted by m5james

Stock downpipes have about 4" of wafer, 1/2" gap and then another layer of wafer. I'm not sure if that big open chamber is good or bad for airflow, but I'll replace them with full 3" once prices become reasonable.

$1300 for standard dp is pretty reasonable roght.

[MissionPerformance]

Originally Posted by F10M5Manual

$1300 for standard dp is pretty reasonable roght.

[MissionPerformance]

Originally Posted by Used2be

This makes perfect sense and I don't know why the various commercial tuners on here don't explain how software accomplishes a mechanical fix to the rattle? I have no expertise on turbos, so my questions come from ignorance, but if the rattle is somehow exacerbated when the catalysts are removed from the DPs, is there some inherent sloppiness in the linkage used to open and close the waste gate? Is there back pressure from the restriction of the catalysts which eliminates the rattle on an unmodified engine? That must be a very hot location, so perhaps sloppiness is required to avoid any linkage malfunction? Could the turbos themselves be designed to eliminate the rattle? Does anyone have a connection at Garrett?

BMW uses catalytic converts that act as silencers for the rattle. Once removed, the noise gets amplified through the catless downpipes and that is a reason why so many people complain. We redesigned the operating principles behind the wastegate control to prevent the excessive slack in the system, and thus in most cases eliminating, and in rare cases reducing, the rattle noise.
Yes, it is "easy" to redesign the turbos in order to get rid of the noise, though not really cost efficiency.

[m5james]

Originally Posted by F10M5Manual

$1300 for standard dp is pretty reasonable roght.

Having had these out and gutting them myself after reading this - http://www.xbimmers.com/forums/showt...ghlight=gutted, half that price is reasonable considering their HP per $ gains are negligible. The only time I'll be having them out next is for a set of 3" to match the rest of exhaust or maybe even 3.5" since that's the next size up I've read about here.

[Used2be]

Originally Posted by m5james

I'm not sure if that big open chamber is good or bad for airflow, but I'll replace them with full 3" once prices become reasonable.

From what little I've read about turbo motors, it seems the turbos prefer as little restriction as possible in the exhaust system. I'd bet your gutted stock DPs are just as HP producing as the aftermarket catless DPs. Do you have the rattle problem or is the noise better muffled with the dual wall DPs? Since I live in a state which doesn't check emissions and won't need the catalysts for that, I might just gut mine also when I do the tune.

[m5james]

No rattle before or after. Removal and gutting was the easy part, it was the realignment for the clamps at the back of the turbos, bolts into the exhaust piping and not crushing/breaking the buttermilk flaky exhaust gaskets while trying to reinstall with two people.

[ssgm1x]

Originally Posted by NightM

Pics vids or never happen

Sorry but its better to show before and after if you can. Otherwise i have a better chance of seeing a pig fly.

100% FACTS....
Wastegate rattle can be resolved by the tuner with an ECU remap. I dont know why it was so hard for some to believe.....lol
...
Wastegate rattle is sometimes always there but with the stock downpipe u may not hear or notice it at all. Wastegate rattle can become more noticable with a Catless Downpipe....and can be resolved sometimes with an ECU Remap by the tuner...

[schnell1982]

Originally Posted by ssgm1x

100% FACTS....
Wastegate rattle can be resolved by the tuner with an ECU remap. I dont know why it was so hard for some to believe.....lol
...
Wastegate rattle is sometimes always there but with the stock downpipe u may not hear or notice it at all. Wastegate rattle can become more noticable with a Catless Downpipe....and can be resolved sometimes with an ECU Remap by the tuner...

I could possibly see the rattle being adjusted by the tuner for electronic wastegate's but for mechanical wastegates the tuner can not manipulate it.
Also, adjusting the wastegate will change the operation of the turbo.. so there is still the possibility of noise being present in my opinion

[ssgm1x]

Originally Posted by schnell1982

I could possibly see the rattle being adjusted by the tuner for electronic wastegate's but for mechanical wastegates the tuner can not manipulate it.
Also, adjusting the wastegate will change the operation of the turbo.. so there is still the possibility of noise being present in my opinion

Mechanical and Electronic wastegate can be adjusted to fix wastegate rattle. Performance may be affected depending on how bad the rattle is. But all tuners and all BMW dealers can make adjustments to resolve this on any type of wastegate. They've been doing it for the last few years for those with wastegate rattle. It may cause some turbo lag but this depends on how bad the initial Rattle is.

[schnell1982]

Originally Posted by ssgm1x

Mechanical and Electronic wastegate can be adjusted to fix wastegate rattle. Performance may be affected depending on how bad the rattle is. But all tuners and all BMW dealers can make adjustments to resolve this on any type of wastegate. They've been doing it for the last few years for those with wastegate rattle. It may cause some turbo lag but this depends on how bad the initial Rattle is.

Doesn't that seem to not be a correct fix ?
Minimize the noise to loose operation of the turbo does not sound right.
You can only adjust the electronic wastegate based off the preset specifications from BMW. There is a service function in the ISTA diagnostic.
It is set in millimeters. Too much adjustment in either direction will set a CEL and the turbo wont function as needed.
Sorry but I disagree that this is a correct fix.
The "fix" on the N54 platform was horrible, the correct fix was improved wastegate parts which came out later after the "adjustment" was only a temporary patch and the noise came right back.

[ssgm1x]

Originally Posted by schnell1982

Doesn't that seem to not be a correct fix ?
Minimize the noise to loose operation of the turbo does not sound right.
You can only adjust the electronic wastegate based off the preset specifications from BMW. There is a service function in the ISTA diagnostic.
It is set in millimeters. Too much adjustment in either direction will set a CEL and the turbo wont function as needed.
Sorry but I disagree that this is a correct fix.
The "fix" on the N54 platform was horrible, the correct fix was improved wastegate parts which came out later after the "adjustment" was only a temporary patch and the noise came right back.

Correct fix ? That is debatable in my opinion. Would u rather spend a couple thousand dollars to fix a rattle noise. Or would u rather spend a couple hundred dollars.

[ssgm1x]

Originally Posted by schnell1982

Doesn't that seem to not be a correct fix ?
Minimize the noise to loose operation of the turbo does not sound right.
You can only adjust the electronic wastegate based off the preset specifications from BMW. There is a service function in the ISTA diagnostic.
It is set in millimeters. Too much adjustment in either direction will set a CEL and the turbo wont function as needed.
Sorry but I disagree that this is a correct fix.
The "fix" on the N54 platform was horrible, the correct fix was improved wastegate parts which came out later after the "adjustment" was only a temporary patch and the noise came right back.

It all depends on how bad rattle is as to whether or not it will effect performance. Average daily driver will not notice anything.

[schnell1982]

Originally Posted by ssgm1x

Correct fix ? That is debatable in my opinion. Would u rather spend a couple thousand dollars to fix a rattle noise. Or would u rather spend a couple hundred dollars.

100% debatable
In my opinion there is minimal adjustment range allowed via the programed range set by BMW and for a purpose.
Yes, a tuner can change those parameters but at what cost ? Loss of turbo operation ? For myself that does not seem correct