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Remmy
24th May 2013, 10:29 PM
So I went out today and had a look at some of the plumbing and how the previous owner has set things up with the Daws valve. After reading several NADS installs and Q&A I think I have information overload so I thought I would ask people in the know.

What I have observed is that the boost jumps up and down from 10 to 0 back to 12psi without even changing the revs.. I give it some welly the revs jump up and the boost will go down then jump to 15 max. At this stage the pyro will jump 100 to 200 deg in a matter of seconds and sit around a max of 450 and will settle around 300 when driving easy with the boost ranging and jumping from 0 to 12 or so at 1500 to 2000 rpm . All too strange to me.

Here is what it looks like under the bonnet.

Picture 1, you can see the red piping coming out of the turbo actuator
Picture 2, you can see the red pipe going into the “Daws Valve” that is on one end of a T piece that’s connected to what I believe is the “Inlet Pipe” to the IC. PLEASE CORRECT ME IF I’M WRONG!
Picture 3, is a close up of the Daws valve with the black pipe (yellow arrow) (& picture 4) following back to the Boost Controller Solenoid and the green arrow is the piping running to the boost gauge in the cab.

So far it looks correct but I’m open to comments.

Here’s where I’m lost a bit.
Picture 5, it looks to have the piping back to the Boost Controller Solenoid just as it did from the factory witch to me seems to defeat the purpose of installing the Daws in the first place.. Comments?
http://i1237.photobucket.com/albums/ff463/jasta70/needlevalvesetup.jpg

In some of the pictures I have seen on the forum here from Chaz the feed pipe from the Daws bypasses the Boost Controller Solenoid taking away its control over the turbo. Is this correct?? And will this have anything to do with the way the boost is all over the shop and the EGT’s fluctuation? Or if you could explain it to me as if I was 5yo, that would be good.

The last picture is my Boost Controller Solenoid and the one from http://www.chaz.yellowfoot.org, considering how the Daws is connected at the moment on my Patrol should I change things to match the picture from Chaz or just start all over again??
http://i1237.photobucket.com/albums/ff463/jasta70/CHAZPIC.jpg

Still all new to me but learning... Sorry if this is a bit too long and been asked before

Any help would be great and if anyone is in the Penrith/Blue Mountains with all the NADS on I would appreciate having a look on how you have done things.

Cheers

Remmy

Rumcajs
24th May 2013, 10:53 PM
Dawes valve doesn't take control of the VNT away from ECU if you leave the solenoid connected. All it does is limits max boost. That's all.
If you want to by pass ECU control you need a needle valve as well.
See pics attached it should be quite easy to follow thats when only Dawes valve is used to limit max boost. If you only have Dawes installed than your current installation is correct.

Rumcajs
24th May 2013, 10:57 PM
To take a control of VNT install needle valve which than by passes the VNT solenoid.
next pic -->

Note: you don't have to fit the needle valve in dash you can leave it under bonnet next to Dawes or existing VNT solenoid so you don't have to run excess lengths of vacuum hoses.

Remmy
25th May 2013, 09:37 PM
Thanks Rumcajs

Will not having a needle valve and just the Daws valve have any effect over the boost control? Reason I'm asking is that on the freeway, 100KPH, tonight I noticed the boost would sit on 12psi and the EGT's were about 300 then the boost would drop down to 5psi and the EGT's would start to rise to 450, all this would happen without even changing RPM. If I then back off the boost would climb and EGT's would fall. Will a needle valve help control the boost and create a more linear boost curve?

Cheers

Remmy

Rumcajs
25th May 2013, 10:24 PM
Thanks Rumcajs

Will not having a needle valve and just the Daws valve have any effect over the boost control? Reason I'm asking is that on the freeway, 100KPH, tonight I noticed the boost would sit on 12psi and the EGT's were about 300 then the boost would drop down to 5psi and the EGT's would start to rise to 450, all this would happen without even changing RPM. If I then back off the boost would climb and EGT's would fall. Will a needle valve help control the boost and create a more linear boost curve?

Cheers

Remmy

There you go, that is exactly why you should fit needle valve. When cruising ECU backs off boost and opens EGR valve full bore so of course EGTs skyrocket.
Cheers

Remmy
25th May 2013, 11:01 PM
Thanks

Cheers

Remmy

mudski
26th May 2013, 12:54 AM
looks like the other members have got it sorted but your pics it looks like its in wrong. Looks like...
Here's a pic of my setup with labelling. Plus it's best to have the Dawes valve sitting vertical so the ball sits true on the spring inside the valve.
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