[PackPride85]

Since it seems this is now adjustable if using BM3, I'm curious if PTF or anyone else knows exactly what that adjustable burble slider in their software is doing? If its retarding timing on throttle lift, can we consider this a very minor anti-lag system? If its adjusting timing and still injecting fuel w/ spark during lift, I would think yes?

[SeanWRT]

Igniting fuel on lift off appears help keep the manifold pressure, but the diverter valve already does just a much better job at it.

DV has been a smart engineering and specially well executed by BMW as you probably notice every single turbocharged BMW has excellent throttle on/off response, with or without burble.

Huracan/R8 albeit being naturally aspirated, pops and crackles like crazy from factory.

Let's believe it's just drama.

[PackPride85]

Originally Posted by SeanWRT

Igniting fuel on lift off appears help keep the exhaust manifold pressure, but the diverter valve already does just a much better job at it. DV works in a way more efficient fashion where the hot and pressurized air (pre-intercooled) gets routed directly from compressor section to turbine, as opposed to going thru all the charging air plumbings (intercooler, throttle and intake manifold), in and out of cylinder and thru turbofold before eventually touch the turbine.

DV has been a smart engineering and specially well executed by BMW as you probably notice every single turbocharged BMW has excellent throttle on/off response, with or without burble.

Huracan/R8 albeit being naturally aspirated, pops and crackles like crazy from factory.

Let's believe it's just drama.

Where did you find that the DV re-routes air to the turbine? The only info I could find on the DV in the N55 was from the technical training doc and it says it re-routes that air back to the inlet side like a normal DV.

[M Fifty]

In addition to creating burbles, injecting fuel on overrun may be being used to cool the exhaust valves?

[SeanWRT]

Originally Posted by PackPride85

Where did you find that the DV re-routes air to the turbine? The only info I could find on the DV in the N55 was from the technical training doc and it says it re-routes that air back to the inlet side like a normal DV.

I looked up yes you're right I stand corrected. In the bmw application DV recirculate charging air within intake system, not to the turbine. Thanks for checking. Post edited.

One more thing indicating that burble won't be necessary for more responsiveness - there is the wastegate to dictate how much exhaust flow is pushing the turbine. And if you read log, wastegate duty % is never 100% outside of spool up. That means if DME wants more turbine shaft speed during pedal lift off, wastegate duty can always increase to achieve that and much more accurately.

[-Eidos]

Reviving this thread... I'm currently running BM3 stage 1 OTS tune with FBO's (Fabspeed sport cat DP, Remus exhaust, etc..) and even the OEM burble settings are now slightly obnoxious for my tastes.

Have there been any new insights regarding the cons to disabling burbles?