My spool sucks, help me!
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From: Granada, Spain
I can't get more than 1-2 psi at 3k rpm no matter how much load i'm putting (also tried brake boosting). I have tried the following thing:
- tighten the wastegate arm
- run with no vaccum hose to the wastegate actuator
- retard spark
- advance spark
- add more fuel
- remove fuel
- retard/avdance vvt cam
- run open downpipe
'01 car with T3 60 trim 0.48 / 0.63, custom log manifold, stock injectors, stock clutch, adaptronic ems.
No intake boost leak, no pre-turbo exhaust leaks... what i'm doing wrong?
- tighten the wastegate arm
- run with no vaccum hose to the wastegate actuator
- retard spark
- advance spark
- add more fuel
- remove fuel
- retard/avdance vvt cam
- run open downpipe
'01 car with T3 60 trim 0.48 / 0.63, custom log manifold, stock injectors, stock clutch, adaptronic ems.
No intake boost leak, no pre-turbo exhaust leaks... what i'm doing wrong?

Plug both ends of your intake (from the turbo to the throttle) and confirm there's no boost leak. There's some examples on the forum- I used some pvc end caps with a tire valve in cap to ad air from a compressor.
Thread Starter
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From: Granada, Spain
I checked for leaks and is not leaking. I'm sure the wastegate is closing because the turbo makes tons of boost past 4.5-5k rpm.
I'm asking myself if the VTCS stuff could be causing the problem. In my car the VTCS is still conected to the stock ecu. I belive that the ecu disconnect vtcs past 60ēC or something... so the question is... since the adaptronic loom is emulating WT signal and I have no idea of the value that are throwing the resistors, maybe the vtcs is always closed and only open when rpm hit some kind of threshold value on the stock ecu.
Anybody knows more about how the stock ecu control the vtcs?
I'm asking myself if the VTCS stuff could be causing the problem. In my car the VTCS is still conected to the stock ecu. I belive that the ecu disconnect vtcs past 60ēC or something... so the question is... since the adaptronic loom is emulating WT signal and I have no idea of the value that are throwing the resistors, maybe the vtcs is always closed and only open when rpm hit some kind of threshold value on the stock ecu.
Anybody knows more about how the stock ecu control the vtcs?
This shouldn't get you sure its closed. If it is a little open, then you will still build enough exhausts at higher revs to make boost, but it won't do at lower.
Thread Starter
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From: Granada, Spain
Past 4.500 rpm the boost creeps very quick.
No locals with T3's unfortunately :(
Same as above, check for boost leaks & check the wasgate to make sure the flopper is closing all the way. If you have an adjustable one adjust it alittle tighter.
Also what psi is the actuator for? Do you have a manual or electronic boost controller? Maybe its cracking open early.
Also what psi is the actuator for? Do you have a manual or electronic boost controller? Maybe its cracking open early.
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From: Granada, Spain
8.3 psi is the factory setting, same as my target boost, but i've tried to tighten to a herculean level...
MBC, also have an EBC but not installed yet.
I have dismantled several times the turbo, and the gate moves freely.
MBC, also have an EBC but not installed yet.
I have dismantled several times the turbo, and the gate moves freely.
So you have tried to tighten the rod that goes to the waste gate flapper? I wouldn't bother with the EBC if the MBC you have is a ball and spring type. It's not going to help. After that check for boost leaks. I've had some silicone connectors fail before and it was hard to find. Also vvt problems are a possibility. Retarded cam timing will make boost build slower, and if it moves enough could cause the problems you describe. (I am not aware of how the later vvt works so I don't know how much of a problem this could cause)
Last edited by vw_nut; Jan 2, 2010 at 11:57 AM. Reason: reread for comprehension
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From: Fake Virginia
I checked for leaks and is not leaking. I'm sure the wastegate is closing because the turbo makes tons of boost past 4.5-5k rpm.
I'm asking myself if the VTCS stuff could be causing the problem. In my car the VTCS is still conected to the stock ecu. I belive that the ecu disconnect vtcs past 60ēC or something... so the question is... since the adaptronic loom is emulating WT signal and I have no idea of the value that are throwing the resistors, maybe the vtcs is always closed and only open when rpm hit some kind of threshold value on the stock ecu.
Anybody knows more about how the stock ecu control the vtcs?
I'm asking myself if the VTCS stuff could be causing the problem. In my car the VTCS is still conected to the stock ecu. I belive that the ecu disconnect vtcs past 60ēC or something... so the question is... since the adaptronic loom is emulating WT signal and I have no idea of the value that are throwing the resistors, maybe the vtcs is always closed and only open when rpm hit some kind of threshold value on the stock ecu.
Anybody knows more about how the stock ecu control the vtcs?
Stock opens the VTCS at 3000 rpm. normally it only stays closed below 3000 and 60C, but if the adaptronic is jackin up your junk, it will cause problems.
but there's an easy way to test it...
On the front of the intake manifold, under the throttle body, is a vacuum actuator (similar to the wastegate one) that pulls the VTCS closed at startup. Just pull the hose off and plug the manifold side so it doesn't leak and see if it improves things.
Hola, saludos a Espaņa si te encuentras ayi. Mira el vtcs es algo como el puero secundario del mazda rx7 n/a y solamente funciona para una aplicacion sin turbo. En el rx7 esta operado de 2 maneras dependiendo de el modelo. La idea es de abrirse a las 4,500-5,000 revoluciones en el RX-7 y me imagino que en los miatas Mazda tuvo una idea similar, nadamas no se exactamente en que tiempo o que contrala cuando se sierra o se abre. Lo que se es que esta operado por una valvula de vaccum. Puede ser que se este serrando especialmente si cambian los niveles de vaccum con el systema de turbo.
Lo que te puedo decir es que desconectes la valvula esa para que este abierto todo el tiempo. Eso es de acuerdo a este articulo que por lo pronto te pueda interesar.
www.mazdaspeedy.com: Removing restrictive VTCS from intake manifold
Lo que te puedo decir es que desconectes la valvula esa para que este abierto todo el tiempo. Eso es de acuerdo a este articulo que por lo pronto te pueda interesar.
www.mazdaspeedy.com: Removing restrictive VTCS from intake manifold














