ok mate, i will give that a go tomorrow afternoon.
sweet. Its frustrating not being able to do more than 100km/h without the EGT's going up near 500 degrees.
So the results i will get from doing that test, will pretty much be what will happen once a needle valve is installed?
apart from reducing the spool rate.
Yes, that is correct. If you can maintain at least 14psi at highway speeds, you're EGT's should be between 350 and 400c unless you're climbing some long hills.Originally Posted by Leighw85
Hey mate, did the test and it worked great! Had about 14-15psi all the time when up to or over 100km/h.
Lower EGT aswell which can only be good.
Correct me if I'm wrong please but I remember reading somewhere i shouldn't have any more than 10psi at 2000rpm? Now with y Dawes valve set to 15psi. I get no boost over 2100rpm bit 15psi at 2000rpm
Ok, that doesn’t make sense. If you have 15psi at 2000rpm, you should still have it at 2100rpm.
When you fit the needle valve, you’ll be able to adjust the spool rate down to give you 6psi at 1500rpm and 10psi at 2000rpm, which is the ideal spool rate. Without the needle valve you won’t be able to do this, so this is why it’s best to fit the needle valve.
A spool rate that’s too aggressive can shorten turbo life over the long term and induce turbo surge in extreme cases. 6psi at 1500rpm and 10psi at 2000rpm are conservative and safe levels for good turbo life while retaining smooth operation and good performance.
Once you get above 2000rpm, it should be safe to go to maximum boost, even as low as 2100rpm, but ideally you should be able to get a more linear boost curve up to 16psi at 3600rpm, which is where maximum power is produced.
Yeah with the car set up normally (not the test you got me to do) that's where my boost goes right down. Between 2000-2100rpm i get the max boost. Then it drops down to about 6-7psi and the EGT's get to about 500 degrees.
So it's not ideal to have 15psi at 2000rpm? Which is what my dawes valve is set to now? Looking on your site, it suggest 10psi at 2000rpm. Which is where i had it set.
Aaaaargh so much to ask and learn hahaha
Last edited by Leighw85; 4th November 2011 at 12:25 AM.
I would leave the Dawes set to 15psi under load if you don’t get limp mode, regardless of revs because your car is an auto and under load the converter will always flair to just above 2000rpm. After you fit the needle valve, you’ll be able to tune the lower rpm boost down slightly so that you get closer to 10 or 12 psi at 2000rpm and it should take a bit more right foot to get it up to 15, but it shouldn’t pass 15psi below 3000rpm. Above 3000rpm, it may climb up a little more.
In my case, I can get it up to 18psi at 4000rpm, but really only go there on the dyno. Occasionally I have been up to around 3500rpm and it reaches 16psi without any limp mode problems. This is close to what you should be aiming for.
So leave it set to the 12-14psi I get at 2000-2200 rpm for now. And get my needle valve and sort it out then?
Yep, that’s the way to go. Just remember to be a little bit gentle on the throttle until you get the needle valve in so you don’t get any big spikes or limp mode problems and it should be good.
Ok picking up my needle valve this afternoon
I've seen your diagram on your site mate, is that what I need to do?
Which hoses from the ecu need connecting up to it, and what ones blocked of?
Also does the needle valve go on a certain way around?
When you install the needle valve, you will also need the small tee piece that came with the Dawes valve. The easiest way is to just take all 3 hoses off the solenoid.Ok picking up my needle valve this afternoon
I've seen your diagram on your site mate, is that what I need to do?
Which hoses from the ecu need connecting up to it, and what ones blocked of?
Also does the needle valve go on a certain way around?
Pull off the long one that went from the turbo to the solenoid, remove the small green damper and fit the hose to the air filter resonator. Put the needle valve on the other end of that hose. The air filter resonator is the other end of the short hose that’s on the solenoid and it shouldn’t matter which way around the needle valve goes.
Then fit the small green damper to the hose that comes from the vacuum pump (the one that you repaired recently) and connect the other side of the damper to the vacuum side of the Dawes valve. Tee off that to the turbo actuator and also the other side of the needle valve and it’s done.
When it's done, there should be no hoses left on the solenoid. Blocking the solenoid ports is optional. I do it just to stop debris getting into the solenoid. but it will all work ok without blocking them.
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