Exhaust flow
05-24-10, 08:39 PM
#16
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Where i live theres a lot of ricers and cops will pull you over for bs like that. So id like a sleeper set up thats why im going with the dual tips.
05-24-10, 08:50 PM
#17
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I'm quoting this from a different thread but if performance is your ultimate goal, here is an excellent guideline. The key to exhaust flow is constriction without restriction.
This information is provided as a guideline to pipe size selection for peak performance at full throttle levels. For vehicles that are street driven on a daily basis, consider using the next smaller pipe diameter for best results.
Smaller diameter pipes will produce low-to mid-RPM torque.
Larger diameters produce mid-to high RPM torque.
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Bigger is NOT ALWAYS better !!
As a general rule, you can enlarge the pipe diameter of your O.E.M. exhaust system by 1/4 to 3/4 inch to increase horsepower. However, any additional increase in pipe diameter is likely to decrease your performance. Improving performance is more about improving air flow than about enlarging pipe diameters.
Smaller diameter pipes will produce low-to mid-RPM torque.
Larger diameters produce mid-to high RPM torque.
------
Bigger is NOT ALWAYS better !!
As a general rule, you can enlarge the pipe diameter of your O.E.M. exhaust system by 1/4 to 3/4 inch to increase horsepower. However, any additional increase in pipe diameter is likely to decrease your performance. Improving performance is more about improving air flow than about enlarging pipe diameters.
05-24-10, 10:09 PM
#18
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I have 3" to dual 3" (w/4" tips), with a resonator.
it sounds mean but its not super loud because of the resonator.
I like the sound of the bigger piping and you can afford to muffle it some, cause when you get on it its gonna roar anyways. even with the 4" tips i don't attract any unwanted attention.
i did 3" to 2.5" once before, but i like the new setup much better.
I wouldn't even mind 4" to dual 3"
it sounds mean but its not super loud because of the resonator.
I like the sound of the bigger piping and you can afford to muffle it some, cause when you get on it its gonna roar anyways. even with the 4" tips i don't attract any unwanted attention.
i did 3" to 2.5" once before, but i like the new setup much better.
I wouldn't even mind 4" to dual 3"
Only bad thing it hangs so low because of the muffler is huge. Its true 3" throughout now. Ill post picture tomorrow.
05-25-10, 11:35 AM
#21
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Please use the chart as a guide. It was taken off a forum for NA cars. Don't worry about the displacement. The important part would be max horsepower.
So for a max of 400hp ==> you will get the best flow with dual 2.5" and single 3.5" exhaust pipes.
It shows piping size for best constriction without the restriction. After 400hp, you're going to actually be restricting flow with dual 2.5" or single 3.5". And then that's when you upgrade the size
Use this instead:
So for a max of 400hp ==> you will get the best flow with dual 2.5" and single 3.5" exhaust pipes.
It shows piping size for best constriction without the restriction. After 400hp, you're going to actually be restricting flow with dual 2.5" or single 3.5". And then that's when you upgrade the size
Use this instead:
05-25-10, 12:37 PM
#22
on an N/A car too little restriction can be a bad thing, and the chart makes sense.
With a turbocharger, exhaust restriction lowers the efficiency of the turbo, so in essence the balance between restriction and max power has completely shifted from where it was on an n/a car. I hope that made sense. there still is a guide though to piping size, its a trade off between spool time and max hp. it will come down to the size of that one center pipe though on a dual setup which for the OP will be 3" either way.
With a turbocharger, exhaust restriction lowers the efficiency of the turbo, so in essence the balance between restriction and max power has completely shifted from where it was on an n/a car. I hope that made sense. there still is a guide though to piping size, its a trade off between spool time and max hp. it will come down to the size of that one center pipe though on a dual setup which for the OP will be 3" either way.
Last edited by Ali SC3; 05-25-10 at 12:43 PM.
05-25-10, 12:52 PM
#23
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No no, I didn't mean to say NA cars needed restriction. All car exhausts should not have any restriction at all, whether it's naturally aspirated or turbocharged. What I meant is that you should have the most constriction without any restriction.
Does that make sense?
Restriction for all cases reduces efficiency and power.
But your right, in a turbocharged car the dynamics change. It then becomes a trade off of spool time and max hp
Does that make sense?
Restriction for all cases reduces efficiency and power.
But your right, in a turbocharged car the dynamics change. It then becomes a trade off of spool time and max hp
05-26-10, 10:32 PM
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Header might do you something but you should get a full cat back. (Not axle back) Its like your leaving everything in the middle stock but changing the front and back only. If your NA you need some backpressure.
05-26-10, 11:24 PM
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That's what I figured. I can't find any bolt-on catbacks online but I guess performance shops can make custom ones. I think I'll check that out.
05-27-10, 11:13 AM
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Headers and leave your stock piping. Get a universal weld on exhaust. You cant except alot of gains per $$$ amount spent for a NA exhaust. You might end up spending $500 on a system for 15hp increase? The plus is you get sound and a nice looking system =P
05-27-10, 11:40 AM
#30
yeah, the best part of the exhaust on the n/a is the look and sound.
thats why I wouldn't go cheap if youre getting one made, because it could come out looking bad/sounding bad. either find an exhaust shop you can trust, or choose between buying a used one or an expensive bolt on.
thats why I wouldn't go cheap if youre getting one made, because it could come out looking bad/sounding bad. either find an exhaust shop you can trust, or choose between buying a used one or an expensive bolt on.