what is tthe advantage of dual exhaust and its cost?
Dual exhaust only has advantages for V8 engines or high output V6 engines, To get the best performance from a dual exhaust you would also need to increase the air intake as well, the two combined increases the efficiency and the horse power of the engine but the ecm will have to be tuned to accommodate the physical changes in the system. So it could get a little pricey.
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