Dual Exhaust
07-15-2002, 12:45 PM
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Dual Exhaust
2001 Hyundai Tiburon...I wanna make it dual exhaust, however did some Searching in the forums and a couple of people said it was a bad idea, but didnt say why, so um...why?!
07-15-2002, 01:03 PM
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Because there is no real benefit. Dual exhausts benefit 'V' engines where there are two separate exhaust manifolds, each of which flows down to its own muffler. Your exhaust is merged into one pipe--splitting this pipe actually adds flow resistance at the split point, and provides no real gain for it.
You just end up paying twice as much. wink
You just end up paying twice as much. wink
07-15-2002, 01:48 PM
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At best, it will do nothing more than a proper single exhaust could do. It could very easily decrease performance though.
Don't mean to rapid-fire answers at ya, I just got done my investing diatribe in off-topic wink
Don't mean to rapid-fire answers at ya, I just got done my investing diatribe in off-topic wink
07-15-2002, 01:48 PM
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My idea would have been to get a 4 to 2 to 1 header and modify it. Keep it two seperate pipes from the header all the way back, running only 2* mandrel into a 2 to 2 high flow cat, continuing to two seperate mufflers. I think this would sound and look good as well.
07-15-2002, 02:06 PM
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Actually, that could sound really odd, and might end up not working too well at all. The flow would be quite uneven in each pipe--you're only getting flow in 2 of the 4 strokes per cycle.
When they converge to one pipe, the four pulses mix and smooth the flow, which helps with scavenging too. If you just have two cylinders together you end up with a series of pulses, depending on how it is piped up. Since the firing order is 1-4-3-2 and they are piped up 1-2 3-4, cylinders 1 and 4 have two strokes between the last exhaust ejection (from cylinders 3 and 2 respectively), so the gas has had time to slow down. The new gas from cylinder 1/4 has to waste energy accelerating the gasses again, and it makes for less effective scavenging at the end of the cycle.
When they converge to one pipe, the four pulses mix and smooth the flow, which helps with scavenging too. If you just have two cylinders together you end up with a series of pulses, depending on how it is piped up. Since the firing order is 1-4-3-2 and they are piped up 1-2 3-4, cylinders 1 and 4 have two strokes between the last exhaust ejection (from cylinders 3 and 2 respectively), so the gas has had time to slow down. The new gas from cylinder 1/4 has to waste energy accelerating the gasses again, and it makes for less effective scavenging at the end of the cycle.
07-15-2002, 02:16 PM
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Indeed. The flow dynamics of an inline four are almost dependant upon the merging of those exhaust pulses for proper scavenging. If we had a better designed cylinder head, you MIGHT get away with the 4-2 header concept.
Outside of a special header and a vastly different cylinder head, an inline motor will generally never benefit from a dual pipe setup. Aesthetically it's your choice, but for performance, keep it single.
Outside of a special header and a vastly different cylinder head, an inline motor will generally never benefit from a dual pipe setup. Aesthetically it's your choice, but for performance, keep it single.