I've tried burning regular gas, and I find the rattling under load to be unsettling. The manual indicates that it won't hurt the engine, but I don't like it. I like the car, and I would have bought it even if it made only, say, 325 hp. I get no benefit from the extra horsepower provided by premium gas, and I'd like to stop wasting money on it. I would like a properly engineered mod to allow me to burn regular without worries. Anyone know how to do this?