Gave In.. N249 Bypass Done...My View

[Bogwoppit]

After reading everyones comments I decided to bypass my N249 valve today. I have only bypassed it mechanically for now, just to see the difference.

To be honest I haven't noticed much difference, but the dv noise is louder than it was before, the noise is more sharp and the "dump" noise is quicker.
My car still has a Seat airbox, but smoothed, enlarged intake and green panel filter fitted.

Gazjones if you want a hand bypassing your valve let me know.

 

[gazjones]

peter yes would like a hand doing it got some pics of mine to see if its the same just changed most of my vac hoses with red ones and have enough left to do this
pics of mine just to see if its the same layout as the mk3

 

[Bogwoppit]

It looks pretty similar, just the inlet manifold connections look in a different place.

Can the red hose that is coming off the top of the dv (between boost gauge T and N249) reach the the other T that is connected to the check valve and front of N249? If it is long enough you shouldn't need to cut anymore vac hose.

 

[gazjones]

i think the dv hose can reach the t off the inlet manifold pipe then i just need to run a pipe from the one way valve to the other gold coloured valve at the back left of the engine bay?

 

[PhilW]

Whats t-pieced into the DV connection? Boost gauge?

 

[gazjones]

yes a boost gauge tried this today and dv sound is crisper and louder swapped it back to normal and less dv noise and tiney bit less boost i think very marginal if any but will be doing it properly now and boost gage seems to work better coming direct from the manifold!

 

[ChrisCurzon]

hey guys

still getting a realyl loud chatter from my dump valve checked all the pipe not kinks and all pluged in correctly did leak test on dv dident move till i took finger off even put old standard 1 on and still did the chatter, my forge valve has a green sprink but even makes the chatter and only like 10 psi.
any 1 know what could be the propblem? every 1 said it sounds good from outside but its loud and bloody anoying hearing it chatter every time i let off on inside lol

 

[PhilW]

Have you got the check valve on the right way round after you done the n249 removal?

 

[ChrisCurzon]

which valve to you mean? the white and balck 1? the white bit is ponting up so think taht rigth way

 

[Sharky_82]

yea thats the check valve - the white should be pointing up -

 

[Olly20VT]

i think he ment DV, i tryed mine on backwards once and it made chater sounds so i put it back.

 

[Molehill_Mike]

Few pics of mine...

Just need to clean the engine bay now...


Mike

Engine bay now cleaned...!

See thread Here



Mike

 

[TTS Roadsport]

Mike,

just a warning. I had the 2 sensors mounted on the rocker in the same way as yourself, and the n112 broke off where you have put the bend in. It resulted in a blown fuse, melted hoses and a new valve. £25 for me, but more for you guys

I have now made a strengthening bracket for the valve so this wont happen again hopefully. I also lengthened the cables for the other valve and relocated it under the scuttle. Looked odd having a valve with nothing going to it.

Pic:

 

[ian_cupra]

did mine a bit ago, noticed a fair difference, mainly between gear changes, seem to be on boost straight away after gear change, its great!!

 

[Molehill_Mike]

Mike,

just a warning. I had the 2 sensors mounted on the rocker in the same way as yourself, and the n112 broke off where you have put the bend in. It resulted in a blown fuse, melted hoses and a new valve. £25 for me, but more for you guys

I have now made a strengthening bracket for the valve so this wont happen again hopefully. I also lengthened the cables for the other valve and relocated it under the scuttle. Looked odd having a valve with nothing going to it.

Pic:

Good work mate. Maybe catch up at a meet in Jan? There is one on the tenth I think...

Mike

 

[bigjode]

why is the one way valve needed if you remove the N249 AND the N112. i thought it was only there to protect the N112. surely if this is removed, then you don't need the check valve aswell?

 

[Molehill_Mike]

why is the one way valve needed if you remove the N249 AND the N112. i thought it was only there to protect the N112. surely if this is removed, then you don't need the check valve aswell?

I'm not 100% but I think if you remove that one then the ECU flags up the error etc, thats when soldering and crap come into the equation. The way its been done on my car and a few others, the ECU doesn't know any different.

Also since removing this valve and resetting ECU, over the last week or 10 days etc, the car has felt better and better, now I hit/peak 21 PSI in 2nd 3rd 4th and 5th gear

I love this car !!

Mike

 

[ChrisCurzon]

hey mike on your i seen you havent done the resistor bit but you have removed that metel bracked where have you put teh over valve that aint plumbed in but its still wired in?

 

[JIMYU]

has anyone seen a drop in boost presure sinse doing the bypass..?

I did mine a couple of weeks ago and lost 2-3 psi.

mind you i did take the shield off the dynatwist at the same time, but i don't think that'd make much difference, especially in winter.

 

[bigjode]

1 or 2 people have actually, but its like 1 person sees a drop, 50 see an improvement.

These cars are unpredictable - you only know what works on your car once you've tried it on your individual car.

The shield on the dyna wouldn't cause a boost drop - the air may be hotter but the turbo boost shouldn't decrease. Infact some say warmer temps cause higher boost as the ECU requests more as the air is less "efficient".