FLASH wrote:Can someone explain the difference between True Dual and...not True Dual Exhaust?
Quite simple actually. True dual means that there are physically 2 separate exhaust pipes going from the manifold at the engine to the rear of the car. Each of the pipes can have their own catalytic converters and resonators to the back of the car, but many cars merge into the same cat only to split back into their respective pipe to the rear, making it fake dual exhaust. True dual exhaust is when 2 the pipes to the rear never come together to share their exhaust gases whether it be in a cat or in free flow.
If you see a car that is factory single exhaust with dual exhaust on the back, that means that either the person had it modded to be true dual, so he routed new piping from the engine exhaust manifold for another pipe to run to the rear. This method is very cost ineffective and usually results in little to no horsepower/torque increase, and only decreases performance. Or the person installed an extender or connecter pipe (long muffler that spans the width of the car in the rear) from the single at the rear, to add another tip on the other rear end side of the car. This picture in this link sort of illustrates what I mean.
http://eisparts.com/Merchant2/graphics/00000001/113251053AJ.gif And this method is just for show, with no performance increase, only decrease as there is more piping the exhaust has to flow out of (due to a reduction in backpressure). Engines from OEM are designed to be either single or dual and should be kept that way to maintain the performance the engine can output. 4 and 6 cyl engines usually get single, while a few 6 cyl do get dual from factory (like the new Honda Accord; no reason for this as there is no performance increase, just cosmetic). 8-12 cyl do dual exhaust as they split the manifold 4 and 4, 5 and 5, or 6 and 6, eaching exhaust manifold bay getting a pipe to the rear.
by hari-bhari » Mon Jul 21, 2003 12:51 pm 
