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Brezno
06-13-2014, 02:54 PM
Hello Guys,
after installing a turbo on my stock k20a2 I can't hold the boost low enough.
For the first I had installed a 0,6bar spring in my wg but the boost went up to 1bar/15psi in the boostcut at 7100rpm...
Now I've the smallest 0,2bar/3psi spring in it and the boost goes still up to 11psi at 8100rpm.

My dumptube is welded into the downpipe could this be the problem that I can't go lower?

I've seen other turbobuilds with bigger turbos and 8 9psi.

Sorry for my bad english, but I'm from Germany.

Spaz
06-13-2014, 04:43 PM
Are you sure your vacuum lines to the wastegate are correct and not backwards? Had a buddy do that and it would spike boost super quick lol

Also no vacuum leaks etc.

Brezno
06-14-2014, 05:41 AM
How could it be backwoards?
I've a "Y" connector at the end of my intake manifold with one line which goes to bov an the other to the wg (44MVR). The one at the wg is installed at side, other sideports are closed and the upper for boostsolenoid are open.

monjarassi
06-14-2014, 02:36 PM
check and see if the solenoid is hooked up this way.

http://www.d-series.org/forums/attachments/engine-management/27801d1306068521-hondata-boost-control-solenoid-configuration-wategateinstall.jpg

Brezno
06-14-2014, 03:46 PM
I've no solenoid, boost is only regulated by wg spring.

monjarassi
06-14-2014, 06:37 PM
so no solenoid and no controller. that explains everything

what turbo manifold do u have?

Brezno
06-14-2014, 08:01 PM
AFI sidewinder and GTX 3076

stigrl06
06-14-2014, 11:19 PM
might be experiencing boost creep

aLmk
06-18-2014, 10:20 AM
so no solenoid and no controller. that explains everything

what turbo manifold do u have?
That doesn't explain anything. If he has a boost/vac source hooked up to the bottom gate that's all that is needed for the wastegate to function properly at spring pressure. Just make sure the top port on the wastegate can vent to the atmosphere.

might be experiencing boost creep
Yea I think this a typical case of boost creep. What size is the wastegate? Picture of the manifold and wastegate neck?

monjarassi
06-18-2014, 10:34 AM
the OP never specified what all he had or has done to the gate so it explains everything.

aLmk
06-18-2014, 10:55 AM
the OP never specified what all he had or has done to the gate so it explains everything.
Explains why he has boost creep problems? Or just explains how it's setup? Based on what he's said he either has a leak in the line going to the bottom port of the wastegate, a leak in the diaphragm of the wastegate, or a poorly designed manifold that is simply creeping.

Brezno
07-22-2014, 06:41 AM
Wastegate is a 44mm MVR.
Now I've welded my dumptube that it's open because I thought there could be too much backpressure between downpipe and wastegate but still boost creep. After that I made a port in the compressor housing for my wg with a shorter line but still boost creep.

Here's a pic of my manifold. I know the position of the wg neck is not the best...
http://imagizer.imageshack.us/v2/280x200q90/746/aab765.jpg (http://imageshack.us/photo/my-images/746/aab765.jpg/)

aLmk
07-22-2014, 09:15 AM
That's why you're boost creeping. Manifold design is the most common cause for boost creep.

Shanket
07-23-2014, 12:57 AM
i have same manifold no creep im on 8 psi also gt3071
https://scontent-a-dfw.xx.fbcdn.net/hphotos-xap1/t1.0-9/p417x417/1525431_10152198690214874_167720057_n.jpg

Brezno
07-23-2014, 07:35 AM
Hmm, which wastegate and spring do you have installed.

BoostedK20
07-23-2014, 11:19 AM
How could it be backwoards?
I've a "Y" connector at the end of my intake manifold with one line which goes to bov an the other to the wg (44MVR). The one at the wg is installed at side, other sideports are closed and the upper for boostsolenoid are open.
As a start, you should never Tee your wastegate and BOV. They should have their own vacuum sources.

check and see if the solenoid is hooked up this way.

http://www.d-series.org/forums/attachments/engine-management/27801d1306068521-hondata-boost-control-solenoid-configuration-wategateinstall.jpg
Follow this diagram when you have a boost controller

Wastegate is a 44mm MVR.
Now I've welded my dumptube that it's open because I thought there could be too much backpressure between downpipe and wastegate but still boost creep. After that I made a port in the compressor housing for my wg with a shorter line but still boost creep.

Here's a pic of my manifold. I know the position of the wg neck is not the best...
http://imagizer.imageshack.us/v2/280x200q90/746/aab765.jpg (http://imageshack.us/photo/my-images/746/aab765.jpg/)

Definitely a creep-able manifold. Seems that this isn't the issue though. Just because it looks like it can creep doesn't mean that's why. Ensure that the vac line isn't kinked and is big enough and strong enough. There are many cases where poor vacuum lines end up collapsing, typically when things are hot. Also, as a rule of thumb, make sure to zip-tie your vacuum line connections. Slip-fit barb fittings alone don't cut it.

Shanket
07-23-2014, 11:58 AM
Hmm, which wastegate and spring do you have installed.

7 psi spring, i have turbosmart 45mm

aLmk
07-23-2014, 12:00 PM
Another thing to note, just because one setup doesn't creep for someone, doesn't mean it won't creep for someone else.

Brezno
07-23-2014, 01:34 PM
I've tested without any wg spring today. The result 12psi boostcut at 7800 rpm in 5th.
After checking the mapsensor I've seen some oxidized pins.

http://img.tapatalk.com/d/14/07/24/ura9ygat.jpg

Brezno
10-18-2014, 11:53 AM
Changed the pins but still creeping...
After installing a second 44mm wg the problem was solved. Now i hold the boost until limiter.
http://img.tapatalk.com/d/14/10/18/8unubu7a.jpghttp://img.tapatalk.com/d/14/10/18/hejemeja.jpghttp://img.tapatalk.com/d/14/10/18/e8aqudup.jpghttp://img.tapatalk.com/d/14/10/18/upa4esa9.jpg

BoostedK20
10-20-2014, 01:19 PM
Nice! Did you do the fabrication yourself? Brezno

Brezno
10-20-2014, 01:42 PM
Yes i did it myself.

PetefromtheStreets
10-20-2014, 09:15 PM
Explains why he has boost creep problems? Or just explains how it's setup? Based on what he's said he either has a leak in the line going to the bottom port of the wastegate, a leak in the diaphragm of the wastegate, or a poorly designed manifold that is simply creeping.
:yeahthat:

aLmk
10-21-2014, 10:55 AM
Changed the pins but still creeping...
After installing a second 44mm wg the problem was solved. Now i hold the boost until limiter.
http://img.tapatalk.com/d/14/10/18/8unubu7a.jpghttp://img.tapatalk.com/d/14/10/18/hejemeja.jpghttp://img.tapatalk.com/d/14/10/18/e8aqudup.jpghttp://img.tapatalk.com/d/14/10/18/upa4esa9.jpg
:thumb:

Jonezy
03-09-2015, 07:16 PM
Holy shit that's brave!

BoostedK20
04-04-2015, 09:11 AM
Yes i did it myself.

How is she holding up?