out of ideas, can't boost over 10 psi

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out of ideas, can't boost over 10 psi

Postby lalojamesliz1 » Wed Sep 27, 2017 12:32 am

I have a stock gen3, I already did a compression check (180,175,180,180), Timing is at 10* and it idles at 1k rpm. 
I did a boostleak test, Installed a mbc ( i plugged the factory boost controller line going back) and it went from 7psi to 10 max no matter how much I turn the knob.
I have a mr2 BPV and before the boost leak test it worked ok besides it staying open and venting until I began to boost. When I did the boost leak it would open and vent but it would open and close automatically when I pressurized my engine. I moved the lines around on the vtv and it stays sealed during the boost leak test but now it won't vent when I boost and let off. 
I'm running a st205 ecu with no cel codes ( i made the diy code 54 harness w/ relay)
I don't know what else to check. I just got this car back and the P.O. had a gen3 installed but he never messed with it and it only boosted 7 psi then I got it back and now I'm here. 
It has a flebay 3" downpipe and it's the same one that I installed when I previously had the car with a gen2 and a regular ct20b. Now it has a steel wheeled ct20b if that makes any difference. Very little shaft play on the turbo.
Please help, Any advice?
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91 Celica all-trac gen3 swap
87 toy 5speed long bed
69 mustang
08 sequoia
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and a 2 car garage :shoots:
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Re: out of ideas, can't boost over 10 psi

Postby underscore » Wed Sep 27, 2017 3:55 pm

Maybe your boost controller can only go up to 10 psi? First fix the BPV, then take the MBC out and hook it to your compressor and see what pressure it starts opening at.
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Re: out of ideas, can't boost over 10 psi

Postby lalojamesliz1 » Wed Sep 27, 2017 7:35 pm

underscore wrote:Maybe your boost controller can only go up to 10 psi? First fix the BPV, then take the MBC out and hook it to your compressor and see what pressure it starts opening at.


It's guaranteed to make 30 psi :P
It's hard to read the gauge on my compressor but it began to open slightly inter 10 and reach it's full extension at about 25. It also holds a vacuum.
Now I'm really lost....
Next I'll try removing the antilag bpv and mr2 bpv and plugging it at the intercooler outlet.
If that doesn't work, I saw someone ask the same thing and people told him to check the cams to make sure they are linesld up. Could that only let me boost to 10-11 if they weren't lined up and off by a tooth?
91 Celica all-trac gen3 swap
87 toy 5speed long bed
69 mustang
08 sequoia
14 avalon
and a 2 car garage :shoots:
lalojamesliz1
Club Member
 
Posts: 158
Joined: Sun Jul 23, 2017 3:03 pm
Location: Bakersfield, CA

Re: out of ideas, can't boost over 10 psi

Postby lalojamesliz1 » Thu Sep 28, 2017 2:28 am

I removed both bpv's and turned the mbc all the way down. Success!
I'm guessing the mbc has a large dead spot were it doesn't increase the boost :shrug: it's almost down all the way!
Tomorrow I'll put the bpv's back on but today I can drive the all-trac to work :smokes:
91 Celica all-trac gen3 swap
87 toy 5speed long bed
69 mustang
08 sequoia
14 avalon
and a 2 car garage :shoots:
lalojamesliz1
Club Member
 
Posts: 158
Joined: Sun Jul 23, 2017 3:03 pm
Location: Bakersfield, CA


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