What size on custom piping??
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What size on custom piping??
Got a Topspeed stainless steel muffler today (looks good/ 5 inch tip also) and I'm going to get the custom piping by the end of the week. The tuner shop told me 2.25'' on the custom piping. Anyone out there with some knowledge dissagree??
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Please report what gains you feel from the exhaust.
How much did you pay for it, and do you have pics?
Also, all I've heard is that 2.25" is the best sized piping to use. Any higher and you supposedly lose back pressure.
How much did you pay for it, and do you have pics?
Also, all I've heard is that 2.25" is the best sized piping to use. Any higher and you supposedly lose back pressure.
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Rep Power: 0 i'm not sure exactly, but i think it's the way the bends are made in the piping 
.....but with crush bent, i think it's a pretty crude way (they just forcefully bend it--?), and it means the inside of the pipe (2.25", for example) isn't uniform throughout. there are parts (the bends), where it is a bit smaller, so there's some restriction. for mandrel bent, they just use a machine that keeps it uniform size throughout, including the bends...... am i right? 
anyone?
btw, 5 inch tip??? woah, i thought my 4-inch was a bit too big. let's see some pics of what it looks like...
.....but with crush bent, i think it's a pretty crude way (they just forcefully bend it--?), and it means the inside of the pipe (2.25", for example) isn't uniform throughout. there are parts (the bends), where it is a bit smaller, so there's some restriction. for mandrel bent, they just use a machine that keeps it uniform size throughout, including the bends...... am i right? anyone?btw, 5 inch tip??? woah, i thought my 4-inch was a bit too big. let's see some pics of what it looks like...
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Originally posted by hassoomi
i'm not sure exactly, but i think it's the way the bends are made in the piping.....but with crush bent, i think it's a pretty crude way (they just forcefully bend it--?), and it means the inside of the pipe (2.25", for example) isn't uniform throughout. there are parts (the bends), where it is a bit smaller, so there's some restriction. for mandrel bent, they just use a machine that keeps it uniform size throughout, including the bends...... am i right? anyone?
i'm not sure exactly, but i think it's the way the bends are made in the piping
.....but with crush bent, i think it's a pretty crude way (they just forcefully bend it--?), and it means the inside of the pipe (2.25", for example) isn't uniform throughout. there are parts (the bends), where it is a bit smaller, so there's some restriction. for mandrel bent, they just use a machine that keeps it uniform size throughout, including the bends...... am i right? anyone?
um ... you don't want any backpressure ... backpressure = bad
backpressure is basically ... bad air flow.
go here ... has some details about crushed (aka pressed) bent piping vs. mandrel
backpressure is basically ... bad air flow.
go here ... has some details about crushed (aka pressed) bent piping vs. mandrel
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mandrel tubbing is the way to go. if you got crush, dont kick yourself over it.. although having crush tubingis kinda like taking a step back, since the stock's mandrel tubing is very well done.
backpressure generally isn't good. although its sorta unavoidable.. the point is to minimize it through efficent exhaust system design (and I'm talking about from the exhaust manifold, aka header all the way tot he muffler)
mandrel tubbing is the way to go. if you got crush, dont kick yourself over it.. although having crush tubingis kinda like taking a step back, since the stock's mandrel tubing is very well done.
backpressure generally isn't good. although its sorta unavoidable.. the point is to minimize it through efficent exhaust system design (and I'm talking about from the exhaust manifold, aka header all the way tot he muffler)
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Rep Power: 338 oh yea.. just make sure that you ask that your original pipes stay intact.. cause most shops have a nasty habit of cutting off the first flange and welding the pipe right on it...
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From: Los Angeles (Downey), California, US
Rep Power: 0 Originally posted by WannaBFast
oh yea.. just make sure that you ask that your original pipes stay intact.. cause most shops have a nasty habit of cutting off the first flange and welding the pipe right on it...
oh yea.. just make sure that you ask that your original pipes stay intact.. cause most shops have a nasty habit of cutting off the first flange and welding the pipe right on it...
Its a celebration bitches!
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From: LA, CALi
Rep Power: 403 yea, so the moral from this post is,
1. mendrel bent is better for better air flowage
2. keep all your stuff when you wanna go back to stock
i love my medrel bent piping... muahaha
1. mendrel bent is better for better air flowage
2. keep all your stuff when you wanna go back to stock
i love my medrel bent piping... muahaha
2k1civic.com O. G.
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Rep Power: 334 ?? i beleive all 2001 civics suffer from the cat or one of the exhuast pipes vibrating wen it rains. like water gets on it and it just vibrates and bangs on the underbody near were your shifter and passenger seat is. its very loud and noticeable.. and thats with stock exhuast.
mine seems to be worste now that i have custom catback
mine seems to be worste now that i have custom catback
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Rep Power: 367 ah search the car troubleshooting forum..
yeah there's a series of civics with that problem..
my 01 doesn't.. but i think someone eventually come up with a solution?
yeah there's a series of civics with that problem..
my 01 doesn't.. but i think someone eventually come up with a solution?
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Rep Power: 527 Backpressure is bad? Um, isn't backpressure responsible for low end torque? That's why everyone's like "don't get bigger than 2.25" piping because you'll lose backpressure and it will suck" or whatever. I know backpressure is bad if you're running turbo, but for NA applications is it still bad?
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Rep Power: 308 Larger Pipe diameters will in no way adverserly affect OUR cars, turbo or N/A.
the only reason i didn't stick 3" pipe on my civic, is becuase it's a pretty tight fit under the car.
Backpressure lets the exhuast gases at low rpms flow faster, which helps torque at lower RPMS.
This is a barely anything with cars that are 2.0l and smaller.
If you have a big block Chevy then thats a whole other story.
All the dyno sheets prove it . bigger pipe is better, period.
the only reason i didn't stick 3" pipe on my civic, is becuase it's a pretty tight fit under the car.
Backpressure lets the exhuast gases at low rpms flow faster, which helps torque at lower RPMS.
This is a barely anything with cars that are 2.0l and smaller.
If you have a big block Chevy then thats a whole other story.
All the dyno sheets prove it . bigger pipe is better, period.
