I am new to the whole turbo scene, and I was looking at the diagram for the boost controller and it says to connect one end to a boost source, and the other end to the waste gate. I connected the boost source to the nipple on the compressor housing, and then connected the other line to the wastegate. Does this sound correct to you guys who are using manual boost controllers? Thanks.



CHRIS

Yes. The wastegate actuator has a spring that will open at (let's say) five pounds of boost. The manual boost controller (MBC) consists of another spring and a ball valve which can be adjusted to keep boost pressure off the wastegate actuator until the boost is sufficient to overcome the MBC spring pressure. The MBC goes in the line from the compressor housing to the wastegate. Be sure it is oriented correctly! It will only work one way. The other way, it won't open and you will see as much boost as your turbo can muster. Be sure to have an accurate boost gauge, and proceed with caution!



And of course you know that you shouldn't be raising the boost level without sufficient fuel and the means to control it, so we'll assume you're good in that department.



Enjoy!

not sure the details on this one, but some wastegates are designed to open when they "see" 5 psi for example, when in reality, your vac lines are at 12 psi for example. this is accomplished by an electronically controlled air valve. the electronic air valve and the ECU will work together to tell the wastegate what pressure to open, but its not necessarily the pressure your manifold "sees". did your set up previously go through one of the air valves on the front drivers side of the engine before heading to the wastegate actuator? if so, you might want to put an air line up against your waste gate actuator and observe what psi it begins to open, and at which psi it is fully open. you might not even have to worry about this, but it might be a good idea to check. if your wastegate operates like this, and you ignore it, you could accidentally overboost a LOT.

I have a Walbro 255LPH fuel pump and an APex'i SAFC to control it. I am going to have it tuned for 8psi. This actually leads me into another question; what can the stock turbo handle for psi? Not that I am going to hit it, but want to stay below it. Thanks.



CHRIS

I have heard that the stock turbos do not run for long on anything much over 12 psi before the center sections start puking oil. Mine was rebuilt and had a larger compressor fitted. I'm currently running around 18 psi without issues, but this car is rarely driven and longevity is not so much an issue for me. Even before the rebuild, I had no trouble hitting 12 psi on the stock turbo.