Thread: Exhaust Poll
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Old 10-17-2013, 10:47 PM   #134 (permalink)
luigi90210
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Quote:
Originally Posted by chii370 View Post
This same thing annoys the hell out of me like those that are absolutely convinced that turbo/SC builds HAVE to have 3in exhaust with no cats, or HFC...... its NOT THAT ******* SIMPLE to just make things bigger with less restriction. please do the research, not trying to be a **** but ive heard this a million times already and almost everyone who says it dont even know why. ive even been kind enough to give you a huge hint. velocity.
I am going to go out on a limb here and say that you are partially wrong about bigger being worse on N/A and supercharged cars and you are completely wrong about how exhausts work on a turbo cars

N/A and supercharged cars: what you want with an exhaust is maximum scavenging, minimal exhaust back pressure, and the biggest possible exhaust size that will provide the most flow but wont cause the exhaust to cool before it leaves the tail pipe

what happens when people slap 4in exhausts on a N/A honda is that the exhaust gas cools half way through the pipe slowing down the velocity thus creating a restriction, but at the same time you dont want a 2in exhaust because it is too small and can cause a restriction

basically you want to find a good diameter sized pipe that not only allows the most flow, but one that will keep exhaust gases heated until it leaves the tail pipe

Turbo: bigger diameter is always better and the shorter the distance, the better the turbo will perform, exhaust doesnt work the same way on a turbo car as it does on N/A and supercharged vehicles, on a turbo car, the more flow, and the shorter the piping, the better the turbo will spool

turbos in a sense are exhaust restrictions, and the scavenging effect is more or less negated, you want to flow as much exhaust out of the turbine as quick as you can because the better the flow, the better the spool, and faster the spool, the faster you make max boost, and the faster your car goes. a popular mod for people to do on their turbo cars is an electric cutout on the downpipe so the turbo spools as quickly as possibly when racing, but when on the streets, you have a tame exhaust that is quiet

im not trying to start an argument here, just stating that you're not 100% correct about bigger being worse and the reasons that you are giving are incorrect(to a point again)
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