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-   -   5psi actuator hitting 10psi-GREDDY (https://www.miataturbo.net/megasquirt-18/5psi-actuator-hitting-10psi-greddy-63842/)

dweezle 02-27-2012 10:48 PM

5psi actuator hitting 10psi-GREDDY
 
2 Attachment(s)
HI Guys

I seem to be hitting like 165Kpa at about 5000rpm on a stock actuator which i believe should only be reaching 5psi.
I have been searching for a few hours on this matter, and have found a few threads with what sounds like the exact issue i am having.
I believe it is called "Boostcreep"? Yeah i am a :noob:
The problem is no one ever seems to post up what fixed it.
The threads just end.

I am running a
DIYPNP
ETD MANIFOLD
GREDDY TD04H Turbo
P630 ACTUATOR (i believe it should be 5psi)
TURBO TONY DOWNPIPE
Stock EXHAUST


Here is a log with at least one solid pull.
http://www.mediafire.com/?j0k8rf2rdc3bc0h

And a quick screenshot.
https://www.miataturbo.net/attachmen...ine=1330400890

Any help would be much appreciated.
It appears the Wastegate opens fully when i disconnect the actuator arm.
The arm is quite tight, but i have left it how i received it.

Thanks guys.

18psi 02-27-2012 10:56 PM

1st make sure its really a 5psi actuator
if it is, then there's 2 options:
port the internal wastegate hole
or
run external wastegate

the former is the cheaper and easier option
the latter is the best option

dweezle 02-27-2012 11:05 PM

Thanks for replying.

I looked for markings on the actuator and the numbers P630 seemed to be the only ones that google found anything related.
That post said it was a 5psi spring.
I will have a search to see how to test the actuator to verify it opens at 5psi.

curly 02-27-2012 11:20 PM

Is it the actuator that came with the greddy kit? If so, it's garbage. I'd highly suggest replacing it with pretty much anything else that will fit before wasting your time trying to fix it.

My boost gauge was jumping all over the place, like, a blurr. I replaced the actuator and it was rock solid, although it tapered off towards red line.

I changed my boost source to Joe Perez's magical source and had rock solid boost all the way to red line.
https://www.miataturbo.net/diy-turbo-discussion-14/boost-sag-no-you-dont-need-ebc-47532/

Bryce 02-28-2012 12:21 AM

You say the actuator arm is very tight fitting onto the wastegate arm? Sounds like it may have a lot of preload on it. Adjust the length of the arm until there is no more preload on the flapper. If it rattles, tighten it just a little bit. TD04s shouldn't need any porting of the wastegate path.

dweezle 02-28-2012 12:31 AM

Thanks again guys.

Bryce, it is so tight i need to force the arm out and over.
Prob about a hole and a half, if that makes sense.

So will do what you said and report results.
Thanks mate.

Bryce 02-28-2012 12:36 AM


Originally Posted by dweezle (Post 840793)
Thanks again guys.

Bryce, it is so tight i need to force the arm out and over.
Prob about a hole and a half, if that makes sense.

So will do what you said and report results.
Thanks mate.

That tight eh? Yeah my money is definitely on 'too much preload'.

hornetball 02-28-2012 12:42 AM

Definitely preload. From the shape of your boost curve, your wastegate is not opening at all.

dweezle 02-28-2012 01:38 AM


Originally Posted by hornetball (Post 840797)
Definitely preload. From the shape of your boost curve, your wastegate is not opening at all.

So when peeps ask how much boost i am running, i can say, "ALL OF IT" :bowrofl:

MY BAD!!

Well it just started Pouring rain here in Sydney, so will go down to the garage and adjust tonight and go for a run tomorrow to test it out if it is not quite so swamp like.
Hopefully this sorts things.

Thanks ALL!!

TorqueZombie 02-28-2012 02:18 AM

Definitaly too much preload. Most I'd go is a half hole of preload then opt for a different can. Other can say if I'm wrong on the half hole thing.

Braineack 02-28-2012 07:44 AM

helper spring.

dweezle 03-01-2012 03:13 AM

Well guys, Thanks.

It seemed to have worked.
I am at about 7Psi but it creeps upto 8 which i expected.
Actuator was too tight!

Thanks again!!

curly 03-01-2012 03:48 AM


Originally Posted by Braineack (Post 840847)
helper spring.

Lol, am i in 2006 again? Good 'ol days of helper springs. My first attempt kept the wastegate open constantly. My second attempt was me replacing the actuator.


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