How much of a difference does it make changing the stock headers and h-pipe to a mac equal length and mac o/r h... with flowmasters... will I notice a big difference in performance and sound? Should I spend the extra money on the equal lengths or just buy the unequal lengths?
Not exactly the same situation, but when I put BBK LT headers and a Dr. Gas offroad x-pipe, there was a huge increase in power . I will admit, that I lost torque below 2,000 rpm, but the difference in the top end more than makes up for it. Above 4,000 is the biggest difference, it just keeps going, and it doesn't hit a brick wall at 5,000 rpm anymore.
anything you can do to make it breathe better is going to give you a boost. between the equal and unequals.. if you dont plan much more modifications in the future, your not really going to notice the difference so go with the unequal. if you have large plans to upgrade cam, heads, intake etc. then I would suggest the equals...
Skip the shorties, they are not worth it. I noticed very minimal gains with my equal lengths, and for the trouble of putting them in, I may as well have put in LTs. Unequal are a real waste of time.