i hear u loose a little low end torque with 2.5in’ but gain more high end. right now i can get 2.25in’ mandrel bent exhaust but i think greddy and thermal make 2g teg exhausts with 2.5in’ piping…isnt 2.5in’ a lil to big for a non-modified natrurally aspirated engine(stock b18a). im just looking for the best gains…
2.5 is too big and it will sound like ****. You can feel the low end loss of power and you cant feel much improvement up top. Personal experience.
2.25 is the biggest I would go, which is what I’m currently running. My friend with same exact teg went 2.5 - when it’s at high revs, sounds like when I eat eggs and drink soda. Go 2.25…as for the mandrel bent, it won’t make a big impact even though it was crush bent. save your money…
the sound difference between 2.25" and 2.5" is not really what you should be looking at. The catalytic converter, resonator, and muffler have MUCH more impact on sound than the piping diameter does. You can have a quiet 2.5" exhaust… you just need the right resonator and muffler. You can easily make a 2.5" exhaust much quieter than the majority of the custom 2.25" exhausts out there, or even compared to the stock exhaust with just an aftermarket muffler. It all depends on what components you use.
Personally, i’d get the Greddy MX. Its 60mm piping (2.36" diameter) so its a good compromise between 2.25" and 2.5". Its a pretty quiet exhaust (not as quiet as greddy sp, rsr, or DC, but still pretty quiet). I plan on getting the MX in the distant future.
How would you make the sound, sound smoother? Does that farting noise at high revs come from no catalytic converter and resonator or it still depends on the piping diameter?
Originally posted by Gerok
How would you make the sound, sound smoother? Does that farting noise at high revs come from no catalytic converter and resonator or it still depends on the piping diameter?
it can be one or a combination of any of the 3. piping diamter will make an exhaust louder (assuming you use the same style cat, resonator and muffler), but not much louder. the majority of sound difference will be caused by different cats, resonators and mufflers.
The raspy sound you hear can be caused by a straight pipe, lack of a resonator, or a really bad sounding muffler. Or it could be some of both, maybe a straight pipe and bad sounding muffler. Or maybe a custom cat back, w/ stock cat, no resonator and a muffler that normally (with a good resonator) would sound decent.
If you don’t want your exhaust to be raspy here is what you need to do you either need to get an aftermarket catback that you know sounds good (most do, but some are loud and raspy). Or if you are going to get a custom exhaust you will need to make sure you get good components. If you change the cat, get a good high flow one. If you decide to go straight pipe you must realize that the exhaust will get louder, and a little raspier (if you have a good resonator and muffler this won’t change the tone too much). Make sure you get a good resonator (a good resonator will substantially cut back the noise level of a custom cat back). And when you choose a muffler make sure you get one that you know how it sounds. Different mufflers have different tones. Two mufflers make look exactly the same, but because of how they are mad they may sound very different. Muffler choice is what scares me most about a custom catback. Its hard to listen to all the muffler choices out there… so its sort of hit or miss. If you buy a name brand one like Tanabe or Apexi you are gonna know exactly how it will sound, but in the end the price for the muffler and all the custom work is going to be about the same as just buying an aftermarket catback.