4 cylinder... Dual exhaust?
Thread Starter
Senior Member
Joined: Apr 2002
Posts: 605
Likes: 0
4 cylinder... Dual exhaust?
You guys think it would be worth it to make an Accent have dual exhaust?
I could buy an OEM header, or the one off of Sharkracing... Or better yet, just get the flange, cause that's all I'd need to get started. Using this flange, I could get someone, somewhere, to weld the right sized pipes to it... But instead of having them go into one exhaust... Have two header pipes go to the right, and two go to the left. No catalytics converters... A pair of flex-pipes, one for each pair of headers... The flex-pipe's exit diameter would be exactly twice that of a header pipe, so when you add the two header exhausts together it is retricted as little as possible. Then run the two pipe out the a$$ end, fabricate any supports that will be needed, and fisish them off with a couple of high flow mufflers. Or just put a shiney tip on them and leave them wide open...
I think if I ever won the lottery that is exactly what I'd do. I don't see why it wouldn't give you some level of increased power...
Any thoughs?
[ September 03, 2002, 07:55 AM: Message edited by: AccentGSi2001 ]
I could buy an OEM header, or the one off of Sharkracing... Or better yet, just get the flange, cause that's all I'd need to get started. Using this flange, I could get someone, somewhere, to weld the right sized pipes to it... But instead of having them go into one exhaust... Have two header pipes go to the right, and two go to the left. No catalytics converters... A pair of flex-pipes, one for each pair of headers... The flex-pipe's exit diameter would be exactly twice that of a header pipe, so when you add the two header exhausts together it is retricted as little as possible. Then run the two pipe out the a$$ end, fabricate any supports that will be needed, and fisish them off with a couple of high flow mufflers. Or just put a shiney tip on them and leave them wide open...
I think if I ever won the lottery that is exactly what I'd do. I don't see why it wouldn't give you some level of increased power...
Any thoughs?
[ September 03, 2002, 07:55 AM: Message edited by: AccentGSi2001 ]
Thread Starter
Senior Member
Joined: Apr 2002
Posts: 605
Likes: 0
Why wouldn't it create power gains???
4 pipes at 1 inch in diameter into one 2 1/2 inch pipe is twice as restrictive as 2 pipes at 1 inch into one 2 1/2 inch pipe.
I'm not talking about huge power gains, but its the same as making a cat-back system with a larger diameter pipe, less restriction, more power.
4 pipes at 1 inch in diameter into one 2 1/2 inch pipe is twice as restrictive as 2 pipes at 1 inch into one 2 1/2 inch pipe.
I'm not talking about huge power gains, but its the same as making a cat-back system with a larger diameter pipe, less restriction, more power.
Thread Starter
Senior Member
Joined: Apr 2002
Posts: 605
Likes: 0
I'm not educated on this subject, so if someone can give an example why this would or wouldn't work let me know. Just don't say it won't work.
Perhaps one of the moderators would like to add something.
So why not have 8 cylinders into one big pipe?
Perhaps one of the moderators would like to add something.
So why not have 8 cylinders into one big pipe?
Member
Joined: Apr 2002
Posts: 54
Likes: 0
From: Harrisburg Pa
Vehicle: 2000 Tiburon
I think the deal with this, at least as far as I can recall from past discussions about this that I've read, is that with a dual exhaust on a 4-banger, there would be too little back pressure, which would rob the engine of low-end torque. The high end might improve, but in all, it would make the car less "driveable" in everyday situations, like stop and go traffic.
Any performance gains would only be felt so high in the engine's rev range that on the whole, it might make the car slower, whether it be a seat-of-the-pants perception or a measurable difference.
If you did a dual exhaust set-up, and modified the engine to get a higher redline, and then added a close-ratio gearbox, then that might set the car up to be a good racer. On that note, not having any catalytic converters would make it illegal to drive the car on the street.
In that case, the car would have to be a good racer, cos you wouldn't be able to drive it anywhere but on the track.
In theory, it sounds like a cool idea, but in practice, it wouldn't work so well.
Any performance gains would only be felt so high in the engine's rev range that on the whole, it might make the car slower, whether it be a seat-of-the-pants perception or a measurable difference.
If you did a dual exhaust set-up, and modified the engine to get a higher redline, and then added a close-ratio gearbox, then that might set the car up to be a good racer. On that note, not having any catalytic converters would make it illegal to drive the car on the street.
In that case, the car would have to be a good racer, cos you wouldn't be able to drive it anywhere but on the track.
In theory, it sounds like a cool idea, but in practice, it wouldn't work so well.
Thread Starter
Senior Member
Joined: Apr 2002
Posts: 605
Likes: 0
I see what you are saying...
Why does there have to be so many variables when it comes to engines... You'd think that if the engine could 'breathe' better, it could create more power throughout the entire rev range... But apparently this isn't the case. So what performance mods greatly affect low end torque, for acceleration purposes. I want to be impressed by acceleration, I don't care about top speed...
Why does there have to be so many variables when it comes to engines... You'd think that if the engine could 'breathe' better, it could create more power throughout the entire rev range... But apparently this isn't the case. So what performance mods greatly affect low end torque, for acceleration purposes. I want to be impressed by acceleration, I don't care about top speed...
Senior Member
Joined: May 2001
Posts: 1,436
Likes: 0
Why so many variables?
Fluid dynamics, thermodynamics, and general mechanical physics. It's not just about quantity, it's also about quality. If you shove air in there in a tangled abhorrent mess, it will not make power.
Exhaust must be built for several items: heat expansion, gas velocity, flow capacity and gas scavenging.
If you make the exhaust too big, gas velocity goes into the basement -- the exhaust moves VERY slowly out of the pipe because it's such a bigass pipe. You also lose any gas scavenging effect because the individual exhaust pulses are lost in the bigass pipe.
Stay single, and on your 1.6L Accent, stay at 2 inches or below.
Fluid dynamics, thermodynamics, and general mechanical physics. It's not just about quantity, it's also about quality. If you shove air in there in a tangled abhorrent mess, it will not make power.
Exhaust must be built for several items: heat expansion, gas velocity, flow capacity and gas scavenging.
If you make the exhaust too big, gas velocity goes into the basement -- the exhaust moves VERY slowly out of the pipe because it's such a bigass pipe. You also lose any gas scavenging effect because the individual exhaust pulses are lost in the bigass pipe.
Stay single, and on your 1.6L Accent, stay at 2 inches or below.