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My question is my friend has a 99 dodge neon R/T (dohc 2.0 L engine). He bought a book from a dealership thar is kind of a performance book that gives you little secrets. Anyways it says for his car buying a full exhaust system (headers, cat, cat back exhaust) will only give you a few HP (like our cars) but if you buy cam gears you will get a lot more HP out of you exhaust system. I was just wondering if that might be able to work on our engines? Or my engine LX model SOHC non v-tec Note that that is for a DOHC engine just as a reminder thanks for your opinions