Originally posted by: sjwaste
Originally posted by: Owls
Please be careful with overboosting the stock turbos. There are lots of reports coming in with blown turbos due to improper modding.
Second that. If this is your first turbocharged car, learn up. Most stock turbos are peashooters that really aren't efficient too far past stock pressures. As efficiency drops, more energy goes into heating the air than compressing it, and that can do some engine damage.
Find out what kind of turbos are on the car, find a compressor map, and learn to read it or talk to someone who does. You can determine what's safe from that.
Boost control is another issue all together. I'm not sure how the 335 does it, if its a mechanical wastegate actuator or an ECU-controlled solenoid (or better yet, a series of them).
Since you bought the car, I assume you plan on keeping it. BMW's aren't exactly the most reliable outside of the warranty period, so if you're going to beat on it, might want to consider selling it in a few years too.
Anyhow, I'm not trying to discourage modding. It's easy to chase some easy HP with a turbo, though, and just as easy to do some damage. Be careful.