N249 - delete or not

[vtraudt]

Has anyone found data (or comparative experience) running with our without the N249?
From memory:
The N249 uses 'stored' vacuum to allow the ECU to send vacuum to the DV, anticipating (likely from gas pedal movement) when the 'shockwave' (from closing the throttle plate) will come to the turbo(s); instead of having to 'wait' until engine vacuum builds up AFTER the throttle plate has closed.

Data might show:
- reaction times from 'throttle closed' to 'DV open'
- pressure spikes in charge pipe (TB to turbo outlet) with/without DV

Experience with/without may show difference in turbo live time?

Or at least: how long have people been driving their turbos with N249 deleted (with or without detrimental effect on turbo live)?

[Mad Cow]

When I first swapped in a 1.8t I didn't have the n249, after I installed it the only real difference was boost came on quicker after gear changes. It was definitely noticeable. There's no downside to having it, only reason to remove it would be to have 2 less vacuum lines, which is a pretty bad reason imo.

[sfl_A4]

There are mass produced original equipment turbo engines out there without a DV or BOV, and they seem to be just fine. I've read where owners on other platforms are ditching their DV with no ill effects, but I don't think there is much scientifically proven data out there to support either side. Seems to be more of a personal preference. Anecdotal feedback seems to be boost is more responsive and immediate after lift-off without a DV, and it simplifies plumbing, eliminates boost leaks. I personally don't intend to mess with the design of the OEM, but to each his own.

[seanf86]

If you have a splitter/bov it acts funny with the n249 at part throttle you can hear the splitter psshhh half assed, I deleted mine on my 1.8t that has a forge splitter and solved that problem. If you don't have a bov/splitter leave it alone.