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

Molehill_Mike

Rollin' on 20s
Jan 3, 2005
2,566
0
Bedfordshire
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.

Thing is a dynatwist is designed to work with a heat shield, whereas an open cone filter isn't... so by removing the shield your actually removing part of the "build" of the induction kit.

I would say put the shield back on and see if you gain those 2-3 PSI back...

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". :confused:

I disagree but also agree on parts lol :confused:
 
Nov 2, 2004
9,335
0
South Wales
I very much dounbt the shield has anything to do with it. In fact it flows a hell of a lot better without the shield. And thats coming from experience.

You've done something wrong or have a boost leak. Log 115.
 

bigjode

Full Member
Feb 25, 2006
504
0
I disagree but also agree on parts lol :confused:


I'm not entirely convinced on it all either - just stuff that i've heard.

But from experience, a change in air filter shouldn't lose 2-3PSI at all. I've tried loads of induction kits with CAI's on and off etc etc but boost was always the same.

Out of interests, I reconnected my N249 and n112 ETC just like the std set-uip this morning and now it only boosts to 18psi - didn't change anything else at all - it normally boosts to 20-22psi without them connected!
 

bigjode

Full Member
Feb 25, 2006
504
0
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

Do you mean since doing the bypass your peak boost has increased? What was it previously?
 

slimjimvw

Newbie
Jul 28, 2006
114
0
Exeter , Devon
Done the mod on my Cupra tonight, as per the pictures in this thread.

First impressions are good , the car is smoother on and off boost (on and off throttle) as it was a little "jerky" before , the DV is working quicker and is definatly louder/crisper as i couldn't hear it inside the car before but i can now.

Also seems to hold boost a little longer to and be less "laggy" between gear changes.

Overall all positive , definatly a worth while mod considering it only takes 10mins :D
 

dj_bigfella

1.8 20vt
Jan 4, 2005
413
0
Hayes, London
www.djbigfella.com
hey people. just read all 8 pages and i gotta say it looks really interesting! just one thing though..... 'TTS Roadsport' mentioned the hoses melting and fuse blowing. if i was to do mine like this (picture below) would i be risking it or is there a way to avoid this from happening? any other people experienced this?



thanks peeps :)
 

slimjimvw

Newbie
Jul 28, 2006
114
0
Exeter , Devon
sorry don't mean to sound paranoid, but there's still that risk isn't it? not really that hands on with cars, just wanna make sure i know what i'm doin! ;)

cheers

If your worried mate get some insulation tube for the silicone , just cover it where its likely to get hot or come in to contact with hot metal ;)
 

T7ODD

Full Member
It looks much tidier and I arranged the hosing so it stayed off the rocker cover and using all the original heat sheathing. I copied Mike's and flipped the valves upside down and bolted them to the rocker cover which gives them alot more support than if they're bolted the 'correct' way up. It looks much tidier now, still dirty though. The dump is much louder than before although I haven't noticed any performance differences as the car still isn't running properly :censored:
Excuse the butchered Dynatwist, I need to get the casing polished up, although it does sound rather nice right now! Maybe I need a nice red or stainless steel filter hehe.

beefyengine1dm.jpg
 

ChrisCurzon

4WD FTW
Apr 9, 2006
1,821
0
Bolton
well worth it i must admit tidys up the engine bay and sounds better once done and seems to have a better pick up.

shouldent take to long for you to do it really only bit i had a problem with was getting the new tube over the forge dump valave nipple.
 

Barry.L

Full Member
May 11, 2006
111
0
Reading
i have just done this mod as well last night, the first impressions seem good. theres slightly less lag between gears and the dv is definetly sounding nicer, plus im only running standard power at the moment. im sure this will have an even greater effect when i get the car remapped.
 
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