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Discussion Starter #1
Hi all!

I have a rev3 JDM turbo which i bought dirt cheap. It has many modifications ill list a few.

Decat, exhaust, cone filter, forge BOV, rev2 engine with Rev3 engine management, poly bushed, supposedly different cams?

Essentially it runs and drives fine byt i was wondering how it should feel hitting boost?

At the moment atound 3k it hits 5psi and then at 4750rpm it will hit peak of about 14psi... is this right or is this extremely late?

Its my first turbo car let alone mr2 so i am not very clued up on all of this...

Thanks in advance for any help you can give!

- Jake
 

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Is your exhaust completely stock with the cat gutted or are there any other modifications to the exhaust? Any intercooler/piping mods? What does the turbo say on the compressor housing ("toyota" or "toyota CT-26")?
 

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There is a possibility that the cams have been degreed in a way that brings power on later in the RPM range. Or you may have a boost leak.
 

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Discussion Starter #6
Is your exhaust completely stock with the cat gutted or are there any other modifications to the exhaust? Any intercooler/piping mods? What does the turbo say on the compressor housing ("toyota" or "toyota CT-26")?
Just toyota
 

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That will explain a lot. As you've pointed out there is no electronic or manual boost controller, it's just waste gate spring pressure which means it should only get about 7psi and probably crack the gate earlier with no control on how fast boost should build. I see you mention it gets 14psi. I mention 7psi as that is what seems to be the recognised max boost for waste gate pressure for a CT26 or CT20b.
 

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Do these suffer the same issue as the 2jz where if you open up the exhaust, you actually raise boost levels due to an insufficiently sized wastegate?
 

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Discussion Starter #13
That will explain a lot. As you've pointed out there is no electronic or manual boost controller, it's just waste gate spring pressure which means it should only get about 7psi and probably crack the gate earlier with no control on how fast boost should build. I see you mention it gets 14psi. I mention 7psi as that is what seems to be the recognised max boost for waste gate pressure for a CT26 or CT20b.
it hangs around 6psi from 3k up to late 4k and builds to 14psi around the 5-5.3k mark. Not sure how but it does. wont go over the 14psi but defo gets "stuck" at 6psi until late rpm
 

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it hangs around 6psi from 3k up to late 4k and builds to 14psi around the 5-5.3k mark. Not sure how but it does. wont go over the 14psi but defo gets "stuck" at 6psi until late rpm
That's your problem. You need some form of boost controller to sort this out of which you are doing.
 

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Discussion Starter #16
That's your problem. You need some form of boost controller to sort this out of which you are doing.
Controller should be here by end of the day ready for install and testing tomorrow.

Only a manual one until I can afford electric but should hopefully completely change my car!
 

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That would be ct20, yes?
Yes. Also, his line bleed line to the T-VSV appears to be still installed (green tube). He's on stock controls. You absolutely need clamps on all of those lines or else you could be bleeding boost from those reference,causing slow spool time and limiting max boost.
My experience dictates you should opt for the AEM TruBoost X-Series, I've got my settings mapped out for various pressure on the CT20b that you can use for a base settings. Your spool up time will be RADICALLY reduced to almost nothing. I'm nearly constantly in boost now with nothing I would refer to as "lag". MPG will suffer but that's the cost of doing business.
 
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