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Car won't hold boost for crap!

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Old Nov 16, 2009 | 07:45 AM
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Default Car won't hold boost for crap!

If this has been asked before and you know which thread it is feel free to direct me.
Ok so my turbo won't hold boost for ****! As soon as I go on boost it spikes to like 16psi then it goes down to 14psi where it should be and by 6k it's down at like 12psi. It really pisses me off cause I'm loosing 10-15 hp at top and my torque drops like a bitch. If you saw my dyno graph it also didn't help that I was going rich at 6k. Soooo what can I do to fix this?
Old Nov 16, 2009 | 08:42 AM
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stock greddy wastegate right? look to replace the actuator or run some helper springs.
Old Nov 16, 2009 | 08:59 AM
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Yes indeedy, my boost needle was all over the place until I replaced the greddy actuator. You'll probably end up with boost creep though. (positive)
Old Nov 16, 2009 | 09:16 AM
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Yep- most IWG actuators start to flake out around double the rating in a boost controlled environment. BTDT. Logging a run with the wg wire shut does wonders for trouble shooting. Just make sure you've got your boost cut where it needs to be for the run.
Old Nov 16, 2009 | 10:14 AM
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Which wastegate do you guys recomend?
Old Nov 16, 2009 | 10:54 AM
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https://www.miataturbo.net/forum/t13351/
Old Nov 16, 2009 | 07:10 PM
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Where are you getting your signal for your wastegate from?
Old Nov 16, 2009 | 09:01 PM
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I replaced my wastegate actuator with one from a new GT2871 and I got boost faster and held MUCH better than the Greddy unit.
Old Nov 16, 2009 | 09:10 PM
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Originally Posted by Fireindc
Where are you getting your signal for your wastegate from?
Compressor
Old Nov 16, 2009 | 11:05 PM
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Originally Posted by miataspeed2005
Compressor
Then check out this thread my friend.

https://www.miataturbo.net/forum/t32479/

Should at least help the issue.. if not resolve it altogether.
Old Nov 17, 2009 | 01:25 AM
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Originally Posted by curly
You'll probably end up with boost creep though. (positive)
If hes not getting boost creep now that means hes got plenty of flow bypassing the turbine so he wouldnt later.

What he has is boost spiking.


Here is where the WG is tied to.. (the line in the background is an oil line and doesnt connect to the wastegate in any way..)
DSCF0043.jpg
Old Nov 17, 2009 | 08:05 AM
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Originally Posted by Fireindc
Then check out this thread my friend.

https://www.miataturbo.net/forum/t32479/

Should at least help the issue.. if not resolve it altogether.
Why is that not a sticky? That is awesome information, I'm going to try that and upgrade my wastegate. Tune my fuel towards redline a little and hit a dyno again should make a 10-15 hp difference
Old Nov 17, 2009 | 09:16 AM
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Originally Posted by miataspeed2005
Why is that not a sticky? That is awesome information, I'm going to try that and upgrade my wastegate. Tune my fuel towards redline a little and hit a dyno again should make a 10-15 hp difference
shoulda looked at how mine is plumbed when you had the chance...



The nipple just before the TB feeds the wastegate actuator. My boost is so steady you can rest your drink on it.
Old Nov 17, 2009 | 09:26 AM
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Originally Posted by Braineack
shoulda looked at how mine is plumbed when you had the chance...
You shoulda looked at mine and helped a ***** out when I was complaining about my boost drop at the dyno
Old Nov 17, 2009 | 09:47 AM
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hahah. or that. I was just trying to find someone for you that knew anything about the DINK ecu.
Old Nov 17, 2009 | 06:23 PM
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Isnt your BOV open at idle/vacuum sir?

Originally Posted by Braineack
shoulda looked at how mine is plumbed when you had the chance...

Old Nov 17, 2009 | 06:32 PM
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a little crack...why?
Old Nov 17, 2009 | 06:41 PM
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Just curious since its still an unfiltered gap
Old Nov 17, 2009 | 07:17 PM
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I don't care about things like that.
Old Nov 17, 2009 | 07:40 PM
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Originally Posted by triple88a
Just curious since its still an unfiltered gap
Does air even get sucked into it? I'm pretty sure the airflow is always out the BOV never in.



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