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Finally got my car put together after buying with blown turbo. has spt intake invidie up, gutted stock dp, no third cat, some home made exhaust, AP stage 2 on 93. Otherwise stock. First test drive i blew the stock intercooler due to not putting in top bolt and intake tube coming off. After repairing the intercooler (TEMP) i drove again and noticed cel flashing cruse and 24psi on the AP. Way over boost. Tried researching but finding nothing. The wastage is not stuck.
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I wonder if the nearly flat plate behind the waste gate on the gutted OEM downpipe could restrict waste flow causing excessive pressure. I'm just a laborer for a construction company but i can put my hand over the exhaust on a Shop Vac and see that causing similar issues if the motor kept spinning at the same RPM.
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Could be an issue. I would plug the green test connectors in behind you passenger carpet and let them cycle. Unbolt the BCS but leave it connected and then blow in each port. Each side should open and close. Also. Do you still have your restrictor pill in the compressor-wastegate line?

 

 

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Updated parts list since original part-out here.

 

Original Full part-out of my LGT HERE!

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Unhooking the EBCS doesn't give you wastegate boost pressure. Linking a line (with no pill in it) from the turbo's compressor directly to the wastegate actuator gives you that.

 

That's what I have but I left the pill in. will the pill change it?

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pill out line from turbo housing to wastegate still boosting to 20 psi. if i slowly go to wot it stays about 16. thinking it has to do with the strait pipe from the turbo back. going to install a catted cnt dp and see if it helps. port wastegate?
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a stock vf40. it was new put on a car by a shop thinking it was just the turbo ended up being the motor. I bought it with less than 5 mile on it. down to only thing left is the wastegate. going to try to swap with my blown turbo.

 

I remember hooking up a low pressure line to mine to make sure it actuates. I don't know if they come adjusted by the factory or not. Just something to consider.

Updated parts list since original part-out here.

 

Original Full part-out of my LGT HERE!

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^^^What he said. The wastegate can't even open all the way with the stock pipe plate-it hits when it opens. Put a downpipe on it and I'll bet the overboost/boost creep issue is greatly reduced. See if someone has one you can borrow just to try.

 

I would bet that BarManBean might just have one. :hide:

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It doesn't matter what the wastegate spring or EBCS was doing... the downpipe's flat plate and turbine outlet geometry prevents the wastegate from flowing enough exhaust to taper boost.

 

Any bellmouth or divorced downpipe will virtually prevent this from happening unless you like to go WOT in 5th at 35mph.

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