318 REBUILD IN 67 BARRACUDA

Since it sounds like it needs boring, choose a flat top piston with four eyebrows with the tallest compression height you can find. Those pistons in it now have a dish and four eyebrows. Low compression. Since you don't have the original engine, let's not be picky and try to keep it original. If it was me, I'd put some 302 castings on it, or 5.2 Magnum heads. Some people scoff at the 302 castings, but as mild as it sounds like you're going, they'll be a nice addition and, unlike the Magnum heads, the LD4B intake will bolt right up to them. With the pistons I recommended, I suspect you could get compression close to, if not a hair over 9:1 and that's just perfect for what you want.