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Weird boost pattern/ secondary boost

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Old May 26, 2011 | 10:16 AM
  #1  
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Weird boost pattern/ secondary boost

I have searched and read many different threads on boost leak and secondary boost problems..

From what I read this is not boost leak? as im getting my full boost on the primary turbo.

Could these be a blocked cat? or what do i test 1st

The car is a 95 JDM.. STOCK.. besides for the exhaust from the cat back..

Any ideas before i go pulling things off?

http://www.youtube.com/watch?v=Cq8fmjTYjjQ (boost gauge is in BAR)
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Old May 26, 2011 | 11:04 AM
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I don't see much wrong here at all.
Stock pattern is 10-8-10 psi, so 0.7-0.5-0.7 bar.

That's pretty much what I see in the video. You're actually getting slightly higher than stock boost.
Then you're getting some high rpm drop-off, to 0.6 bar (9 psi) but that is normal.
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Old May 26, 2011 | 11:11 AM
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Ok but if you look after change over it goes to .8 for a second and drops to .6? it bleeds off a bit from .6 on the high rpm..

Why isnt it holding the .8 or even .7 after change over?

or should i not be to worried and slap some boost controllers on"?
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Old May 26, 2011 | 11:45 AM
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It's never going to hold at .7 at high rpm's, all cars drop off a little to about .6 when you get close to redline, so that's perfectly normal.
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Old May 26, 2011 | 11:59 AM
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^Exactly.

I wouldn't be worried.

But, if you really want 10psi to redline, then you'll have to take boost control away from the stock ECU, either by installing a boost controller or a needle valve(s).

I'm currently running a needle valve in the WG line, and it gives me a bit more boost. But, the ECU is still controlling the WG, so I still get some dropoff.
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Old May 26, 2011 | 12:27 PM
  #6  
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Awsome new thanks guys.. was a bit scared there!!! There is a setup on here a member came up with that I knw work.. using the hallmans RX manual controllers soo im going to do that! and ill see .8 all the way to the red line.. time todo some shopping!

Just didnt wanna go and do this an I did have a problem soo I would rather confirm it on the forum! thanks for the help!!
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Old Nov 28, 2011 | 07:23 AM
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Hi, All im having almost the same problem but i have spikes... sometimes my boost is getting spikes of 0,9 bar

I've made a video

http://www.youtube.com/watch?v=rJ3BO_mJmxU

I', really worried about it... i don't want a blown motor
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Old Nov 28, 2011 | 07:45 AM
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Originally Posted by Arthas
Hi, All im having almost the same problem but i have spikes... sometimes my boost is getting spikes of 0,9 bar
What's your boost controller set up?
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Old Nov 28, 2011 | 08:28 AM
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Originally Posted by Barban
What's your boost controller set up?
I think i don't have a boost controller... I've my car for about 3 months... and I just have started with reliability mods... like... installing gauges, replacing ast tank, as it is a jdm car i didn't need to replace downpipe, and it comes with greddy airinx intake, catback and greddy type S blow off valve...

I'm in trouble? ???
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Old Nov 28, 2011 | 09:34 AM
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Originally Posted by Arthas
I think i don't have a boost controller... I've my car for about 3 months... and I just have started with reliability mods... like... installing gauges, replacing ast tank, as it is a jdm car i didn't need to replace downpipe, and it comes with greddy airinx intake, catback and greddy type S blow off valve...

I'm in trouble? ???
A stock computer with those mods is probably what's causing the spikes. If you want to try a simple fix, buy a cheap manual boost controller and connect it to the wastegate. Until then, you shouldn't boost the car that much or it could blow the motor.
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Old Nov 28, 2011 | 09:45 AM
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Originally Posted by zeroG
A stock computer with those mods is probably what's causing the spikes. If you want to try a simple fix, buy a cheap manual boost controller and connect it to the wastegate. Until then, you shouldn't boost the car that much or it could blow the motor.
well honesty im looking for the easiest solution for it... and manual boost controller sounds a bit.. complicated... and unsafe... what about a electronic one? wich one is better? and easier to install...

the main problem is... here on spain we don't have so many reliable rotaries workshops... there is just a few... and 1 of them is a bit far away from me... so i have a friend with a small workshop... but as you can imagine... on rotaries... he will be able to handle only simple things...

Please help me!!
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