3.4 sounds just about where you wanna be. Although since you're in Michigan and fall is right around the corner I'd just run a 3.5. The difference in power is negligible but you'll be a little safer come the winter months. Just remember when you say you're getting a 'good' tune, that you actually get a good tune! Run a safe AFR and reasonable amount of timing. What's more important to you, being able to romp on the car wherever whenever, or making 10whp more for 1 pull then knocking to oblivion for subsequent pulls?
Good luck! Headers, pulley, tune cars go pretty good for a DD!
