I had a '72 Duster once with a slant auto. We put a super six on it, cut the head .100, mild bowl hoggin, 3.55's, and 2.25 exhaust off of the bigger outlet manifold.
I didn't take it to the track, but of all my trips to the track and experience, I say high 15's. We did race it "out of town" against a '91 Dynasty of mine that I took to the track and ran 17.20's. Wasn't even a race, the Duster tore it up easily.
