Vagcom results after N249 bypass and reversed DV

Westy

Westy

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I ripped out all the N249 gubbins today and reversed the dv to see what effect it will have. These were my results:

before:

257 bhp
271 lbft
boost spiked at 20 psi then held at 18.5 psi

After:

245 bhp
271 lbft
boost peaked at 22 but then it gradually dropped off to 15 psi by 5500rpm!

I'm guessing that my N249 was faulty because I used to get a fluttering noise that has now gone but maybe the reversed dv is leaking boost.

Any thoughts?
 
Ok I'm a bit miffed! I've just done another run with my DV back to the normal position and I got almost identicle results to having a reversed DV:

247bhp
274lbft
22psi from 2800rpm to 4100rpm then it starts dropping off till it reaches 15psi at 6000rpm!

Now how was I getting 257bhp 6 months ago on a warmer day (12 degrees) with less boost with the N249 connected? Could it be that where the N249 is no longer able to open the DV I'm holding more boost and my standard tip is collapsing at 4000rpm?

any suggestions guys?
 
Westle said:
Ok I'm a bit miffed! I've just done another run with my DV back to the normal position and I got almost identicle results to having a reversed DV:

247bhp
274lbft
22psi from 2800rpm to 4100rpm then it starts dropping off till it reaches 15psi at 6000rpm!

Now how was I getting 257bhp 6 months ago on a warmer day (12 degrees) with less boost with the N249 connected? Could it be that where the N249 is no longer able to open the DV I'm holding more boost and my standard tip is collapsing at 4000rpm?

any suggestions guys?
Click to expand...

how are you working out your BHP figure?
 
Nice one for testing this out Westle. I reversed my DV and it feels exactly the same as when it was the normal way around but obviously it has the loud chirp noise.

Will be good to see if there are any differences when you get your lil problem checked out and tested again.

Keep us posted :thumbsup:
 
Well I am running a yellow spring in my DV as opposed to the standard green one so I dont know if that makes any difference but reversed and normal produced near identicle results.

It appears that my timing is being pulled from 4krpm onwards which ties in to my boost drop above so I'm trying to understand what could be causing it!
 
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