Need a snappy comeback

Apparently the only motor that anybody thinks comes in my car is a 340. Or maybe it is the most desirable. Every person who sees my car asks me " what do you have in it, a 340? " It's getting late in the year and it is getting more and more annoying. I usually tell them I don't have anything that tiny in it. I need a snappy comeback, and I don't want to say it's a slant six. Any ideas?