[NeighborsComplaint]

I had a '65 Lemans w. 326 2bbl and single exhaust as a kid. A dual exhaust was a big upgrade in performance. I then added a 4 bbl intake and Carter AFB which also made it even better with no other changes. I was amazed at the transformation which included basic, quality tune up parts. It was a 3 spd w. Hurst linkage and would chirp the tires in 2nd and 3rd with ease. If you're up to a cam swap, a Summit 2801 kit with lifters and springs and a new timing set will give a nice performance return on investment. The 670 heads aren't needed for what is just a nice torquey cruiser. The rear gears would be a better investment than the heads if you had to make a choice.