If you haven't discovered it already, go to Jolly's site for the details on the 305. http://www.6066gmcguy.org/performance.htm

As for an intake for dual carbs, you would have to make one. And like moneypit said, the 305 was made to pull heavy loads at low speeds. If you want to run it wide open on the highway, it won't last. If you're going for performance, a V8 will make you a lot happier.


Fred
52 3600
69 C-10