Yea, you will definately need to reduce the timing, especially if you don't have a Bipes or MSD timing puller. Otherwise when you get into boost you will get the dreaded Pinging and kaboom!
Look into getting a timing puller. They pull timing as your boost increases. This enables you to keep timing for more low-end torque. MSD will pull up to 6deg at 8psi, and is not adjustable. However, the Bipes unit is programmable and has the capability of pulling far more timing and is a much better unit. I'd upgrade from the MSD that is on my Silver car if I were too keep it.