Noob Boost Controller Question

[sauccarl]

Ok so I wanna make sure before I buy a boost controller. Lets say a turbo is SET at a certain psi level, for example: I have the Greddy TD04H 15G turbo that's set at 9psi. So this is what I'm trying to figure out: If I get a boost controller, either Manual or Electronic, I won't be able to LOWER the psi level, only RAISE it. Is this true?

[dreadlocks]

true, you would have to alter the wastegate to lower the boost.. a boost controller cannot do that for you

[saabracr]

Nearly all internal wastegates are adjustable- you can set it for lower boost. How much lower depends on the spring in the wastegate actuator.

[sauccarl]

So how do I "ALTER" it?

[dreadlocks]

it depends, what kind of wastegate? Like saabracr said, Internal ones almost always have a rod and bolt that are adjustable. If you have an external one, like a Tial 38mm for example.. then you replace the internal spring. The wastegate is what controls your boost, a boost controller manipulates the vacuum/pressure source going to the wastegate.. If you plan on running one boost level all the time then just set your wastegate aproprately.. A boost controller is used when you want flexability in adjusting boost levels or your looking for quicker spool time and want to keep your wastegate closed until the last possible moment. They also come in handy for getting rid of boost spikes and leveling your boost levels out across your power band.

I use an electronic boost controller and the smallest wastegate spring I can get away with.. This allows me to change between preset boost levels on the fly, this makes my car more drivable because crazy power/torque is not always desirable. I have 3 settings, Stage I (5psi), Stage II (11psi), and Stage III (17psi).. Stage I is perfect for WOT runs down a curvy road, little risk for traction loss.. Stage II is perfect for daily driving, gives me more power than most cars on the highway. I also use it when launching for 1st-2nd gears for better traction. Stage III is used when I want to have some fun, I use this for lots of reasons but I use it sparingly.