someone mentioned that you could but i dont know if thats true.... i figured you would have to buy a boost controller but was just checking up on it.
Since you have an 03, it's actually completely safe to run about 15 to 16lbs without any other mods. Your car does not have the large delay between open loop and closed loop programming and that's what blow motors when you mess with the boost without tuning. But to keep it safe you need an reputable brand manual boost controller and a good boost guage to monitor at the minimum. A more expensive electronic boost controller that will not allow over the preset amount would be better but will cost over $350 compared to $100 for a GFB manual and an Auto Meter boost guage. I ran 15lbs on my 02 for just over 65000 miles and had no problem. You really don't feel a bump in power but it helps hold boost to red line. Let me tell you though. The day I got a tune with a full turbo back exhaust was awesome. That made a huge difference in power so it may be better for you to just save the money for that in the future.
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