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View Full Version : Dawes and needle valve set up



Remdogg
17th December 2014, 06:54 PM
I have just fitted 3" exhaust, dawes and needle valve, boost and pyro gauge. Gave it a boot full up a step hill and egt's sat on 450 and went up in 4th instead of 3rd so i'm happy with that. The boost seems to spike a bit to 17 psi then settles on 15 psi. Is that normal. I opened the needle valve a bit more but it slows the car to much.

Should i just be happy with that because it is driving nice.

Stropp
17th December 2014, 11:04 PM
Mate if it's driving nice and the pyro temps are good leave it as is, but I'm sure other wiser people will let you know if I'm wrong.

mudski
17th December 2014, 11:05 PM
I have just fitted 3" exhaust, dawes and needle valve, boost and pyro gauge. Gave it a boot full up a step hill and egt's sat on 450 and went up in 4th instead of 3rd so i'm happy with that. The boost seems to spike a bit to 17 psi then settles on 15 psi. Is that normal. I opened the needle valve a bit more but it slows the car to much.

Should i just be happy with that because it is driving nice.

Everything looks good there mate. The needle valve, assuming you purchased the kit from my eBay store, is very touchy. You could open the needle valve just a touch more to slow down the spool up just enough to stop the bounce. But its it goes good don't worry.
I would try to up the boost though. Wind in the Dawes valve until you hit limp mode, then back the dawes off a touch so your max boost is just under the limp more threshold. You may need to play with the needle valve again after doing this. But at 15psi you want around 10spi at 100k's, have the boost too low at 100k's will equate to high EGT's. Which is a common cause of these motors to go bang. To high boost and your just over working the turbo for nothing.
But. It you get a high max boost you will need to raise the cruise boost level too, because if you don't, your spool up rate will be way too slow and the turbo will be unresponsive. I run 25psi max and around 15-18 on the highway. I tried lowering the cruise boost but the car went like a sack of spuds.

But at the end of the day if your happy with that then stick with it. I will say though if you do up your boost levels your EGT's will drop too. The lower the EGT's the better.

Cheers.
Mark.

Remdogg
17th December 2014, 11:46 PM
Just went for a spin. Boost at 22 psi still spikes a bit to 24 but compared to what the ecu was doing its way better. Same hill egts down to 390. It's a little cooler being night time. I'll have another play tomorrow when I'm a bit more sober. Apparently my gf isn't as interested as I am and wanted to go home.

mudski
18th December 2014, 09:25 AM
Just went for a spin. Boost at 22 psi still spikes a bit to 24 but compared to what the ecu was doing its way better. Same hill egts down to 390. It's a little cooler being night time. I'll have another play tomorrow when I'm a bit more sober. Apparently my gf isn't as interested as I am and wanted to go home.

haha! My wife has got the shits with me as every night this week after work I have been doing late nighters til 1am just fixing stuff from Sundays adventures. As for the setup, close off the needle valve just a touch more to slow the spikes, but what I have found is that the higher max boost you go the harder it is to slow the spikes.
Just play a round with it, you may even find having a lower boost level to 22psi, your car might even go better. Depending on how the turbo condition is. Mine is on the top end of usability, probably even a bit too high, where the turbo is just pumping hot air and not doing much. Maybe one day I'll take it for a dyno to see exactly where the sweet spot is.

Rock Trol
18th December 2014, 10:51 PM
Remdogg, is you car a CRD or DI? Mine is a CRD and it peaks at around 16psi under hard acceleration but then goes down to 14. At 100kph it sits between 11 to 12 psi. Car feels really good. If I try and lower the spool rate to get the cruising boost slightly lower the car does not feel as good. Higher boost does not seem to make it run better so I think tune by the way the car feels is important. They are all different.

Remdogg
19th December 2014, 09:13 AM
Remdogg, is you car a CRD or DI? Mine is a CRD and it peaks at around 16psi under hard acceleration but then goes down to 14. At 100kph it sits between 11 to 12 psi. Car feels really good. If I try and lower the spool rate to get the cruising boost slightly lower the car does not feel as good. Higher boost does not seem to make it run better so I think tune by the way the car feels is important. They are all different.

It's a crd. Mine doesnt go any better after about 16 psi but the egts did come down a bit with higher boost. I'm considering getting someone to set it because I tried that many settings I can't remember what was best.