It sounds like you really put yourself in a bind... Your throwing mismatched parts onto an engine that was never designed to be a big performer from day one. You really should reconsider just getting a 350 or 403 it really wont kill you on fuel if thats what your biggest concern is. Just think about it this way, you would be buying all of the same parts for a 350 or 403 and in the end spending about the same amount of money if not less than you are with the 307. Its just not an economical engine to try and get high horsepower out of. If you threw the same parts at a 350 or larger it would toast the 307 with the same mods and still knock down decent fuel economy. Also, stick with the Q-Jet olds motors like them. I had an edelbrock on my car for a while and hated it so I switched back to a Q-Jet. It ran the best for me and got the best mileage, and still does on my 350. Like FE3x said a performer rpm intake will clear the stock hood, I'm running one on my 350 with no problems at all.
