Im gonna scoop up a new Apex'i N1 Muffler here soon and am just gonna have a local shop i go to make my catback piping for me....im thinking of going 2.5", i am 90% sure im boosting my SI this summer...ive been getting different opinions from everyone around, some say 2.5", some say go 3".....what do you guys think?
Will 2.5" Exhuast Piping be alright when i turbo my SI...
- Thread starter SiLvErCiV
- Start date
I say go 3"
deez said:
was just wondering....sounds good though, looks like ill go with the 3"....is the Apex'i n1 turbo muffler alot bigger than the NA one?...im not sure which one i wanna get, i love the look of the smaller one though, i was never one for a big muffler.
my evo has 2 and a half and im boosting it i think it will be fine
yeah get the 3 inch tubing but get a 2.5 n1 ( the 2.5 is the n/a muffler and the 3 is more for f/i) so that you can have a little more back press, the 3 inch n1 is better for cars like 240s with a SR20det, supras and other cars with bigger motors, plus your car will look stupid with that big ass n1Shiznit028 said:
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hmm....this seems to be going back and forth....im not really trying to lose power while im piecing my kit together, i mean it might take a while....i think i may just go with 2.5"....and down the road when im boosted, if i feel im losing power, ill strap on the 3 inch piping.. 
idea: you could find a used (and much cheaper) but still in good condition 2.5" system for now, then when you boost her you sell the 2.5 and get your money back (or at least most of it), and spend the real money on a true 3" system. best of both worlds baby think about it...
[or just wait til you're boosted to get the 3" piping cuz summer's not that far off, and you're gonna want 3 when you're boosted.]
think about it...[or just wait til you're boosted to get the 3" piping cuz summer's not that far off, and you're gonna want 3 when you're boosted.]
Definitly a good idea....but where the hell am i gonna find a some used 2.5" catback piping to toss on my SI...any ideas or anyone know of anyone???civic betty said:idea: you could find a used (and much cheaper) but still in good condition 2.5" system for now, then when you boost her you sell the 2.5 and get your money back (or at least most of it), and spend the real money on a true 3" system. best of both worlds baby
[or just wait til you're boosted to get the 3" piping cuz summer's not that far off, and you're gonna want 3 when you're boosted.]
search classifieds online, ebay, etc for those brands of exhaust that use 2.5 or 2.25 in piping. i know "thermal" makes a 2.25" catback (CL or ST system). or you can find someone selling a custom made one with the piping you're looking for. seeing as it'll be used by you for only a short time, you can kinda go cheap on this buy (i know not usually a good idea for mods). remember, you'll basically be getting your money back in the end, and it won't be on there long if you're getting the turbo in the summer. you can check clubsi.com or other civic sites, ebay, google, i don't know really. i have to do the same myself b/c i won't be getting mine for a while, and i want the exhaust now. good luck!
i was reading up on turbos for my boost setup and thought this would be usefull info to you
Exhaust System
The goal of a good exhaust system is to minimize back pressure. Back pressure prevents the turbocharger from spooling up freely creating lag and a loss of power. The key to minimizing back pressure is to use straight through mufflers, mandrel bent piping, and larger than stock diameter pipe. The turbocharger itself acts as a good muffler, removing as much as 1/3 of the noise from the exhaust system. The first component that requires consideration are the mufflers. Mufflers that have a straight through design do not have internal baffles. The ideal straight through design will have a perforated core instead of a louvered one. Louvers protrude into the exhaust flow to muffle the noise. Perforated cores have holes in the center pipe that do not inhibit exhaust flow. Another thing to look for in a good muffler is stainless steel packing. Stainless packing will not burn out of the muffler like fiberglass (which is used in most aftermarket mufflers) will. MagnaFlow makes excellent universal mufflers that meet these requirements. Of course the best muffler in the world will not make any difference if the pipe diameter is small, restricting gas flow. Two factors effect exhaust flow, the type of bend used and the diameter of the pipe. Two types of pipe bend are crush and mandrel. Crush bending works by crushing the pipe at the bend, in effect, putting a kink in the pipe, reducing the diameter of the pipe at that bend. Mandrel bending works by stretching the pipe as it is bent. The result is a bend that does not reduce the diameter of the pipe. As far as diameter goes, bigger is better, but up to a point. The Corkey Bell book "Maximum Boost: Design, Testing, and Installing Turbocharger Systems" suggests that the full benefits of 3" diameter pipe will not be fully realized until 700 horsepower! To learn more about why, pick up the book. Clearance with the rear suspension can also be an issue with 3" pipe, especially if the car is lowered. If you choose to have a custom exhaust system made and crush bending is the only option (mandrel bending machines are expensive so a lot of shops do not have them) then 3" would be the way to go. The extra diameter will compensate for the diameter you lose when crush bending. If you have access to mandrel bending services then 2.5" diameter pipe is ideal to use. The 2.5" pipe is good to 500 horsepower.
http://www.beesandgoats.com/boostfaq/g2icturbo.html#Exhaust READ THIS BEFORE TURBOING, GREAT INFO HERE
Exhaust System
The goal of a good exhaust system is to minimize back pressure. Back pressure prevents the turbocharger from spooling up freely creating lag and a loss of power. The key to minimizing back pressure is to use straight through mufflers, mandrel bent piping, and larger than stock diameter pipe. The turbocharger itself acts as a good muffler, removing as much as 1/3 of the noise from the exhaust system. The first component that requires consideration are the mufflers. Mufflers that have a straight through design do not have internal baffles. The ideal straight through design will have a perforated core instead of a louvered one. Louvers protrude into the exhaust flow to muffle the noise. Perforated cores have holes in the center pipe that do not inhibit exhaust flow. Another thing to look for in a good muffler is stainless steel packing. Stainless packing will not burn out of the muffler like fiberglass (which is used in most aftermarket mufflers) will. MagnaFlow makes excellent universal mufflers that meet these requirements. Of course the best muffler in the world will not make any difference if the pipe diameter is small, restricting gas flow. Two factors effect exhaust flow, the type of bend used and the diameter of the pipe. Two types of pipe bend are crush and mandrel. Crush bending works by crushing the pipe at the bend, in effect, putting a kink in the pipe, reducing the diameter of the pipe at that bend. Mandrel bending works by stretching the pipe as it is bent. The result is a bend that does not reduce the diameter of the pipe. As far as diameter goes, bigger is better, but up to a point. The Corkey Bell book "Maximum Boost: Design, Testing, and Installing Turbocharger Systems" suggests that the full benefits of 3" diameter pipe will not be fully realized until 700 horsepower! To learn more about why, pick up the book. Clearance with the rear suspension can also be an issue with 3" pipe, especially if the car is lowered. If you choose to have a custom exhaust system made and crush bending is the only option (mandrel bending machines are expensive so a lot of shops do not have them) then 3" would be the way to go. The extra diameter will compensate for the diameter you lose when crush bending. If you have access to mandrel bending services then 2.5" diameter pipe is ideal to use. The 2.5" pipe is good to 500 horsepower.
http://www.beesandgoats.com/boostfaq/g2icturbo.html#Exhaust READ THIS BEFORE TURBOING, GREAT INFO HERE
