Invidia N1 Catless, Turboback vs. Catback


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Now keep in mind, the Cat-Back Exhaust (CBE) is largely a question of personal preference, as power is added from the downpipe with only (at most) 3% being from any CBE. Changing CBE's of comparable size, flow, and quality will be a negligible difference. Additionally, there are little differences in terms of power between catted vs. catless downpipes according to Pete over at EFI Logics. If your more interested in knowning about catted vs. catless downpipes, simply do a search and get reading. Choosing a CBE is largely based on sound and appearance.

The N1 exhaust is actually what first called my attention to STi's. The rumble (caused by the unequal length of the exhaust manifold as I learned later, not the flat boxer style of the motor). I remember it distinctly, a blacked out hawkeye (06/07) STi pulled up to WaWa back when I had my VR-4 Gallant, this is when I still knew little about cars, and I remember being massively impressed at the noise coming from the black car with the parking bench and hood scoop. I looked at the exhaust and love both the angle that it came out on and that it was not as big as some other exhaust I have seen.

After buying my STI it was naturally the first change I made, swapping my APS CBE for a Invidia N1 race. The sound was much more aggressive then the APS, and the volume increased 5x over the APS which makes the N1 about 8x over stock. The tone, rumble, styling, and noise at WOT make this my personal favorite of the GD exhaust options. Not so large as to be a melon cannon (coughHKScough), but just as vocal with a much better appearance.

I have seen on this and other forums many times questions such as "How much louder does the downpipe make it?" or "Does it change the tone", "Will it drone too much?" etc. Upon installing my Invidia catless bellmouth style downpipe, I discovered that the things that initially made me choose the N1 were magnified. I'd say overall its now 10x louder then stock. The rumble is still there, but more aggressive sounding. The overall tone is retained, and the volume isn't massively "magnified" but it is louder. It's as if I've uncorked the exhaust. It carries farther and hits harder. A slight rasp is added which I feel only adds to the overall appeal of the exhaust, giving it a very aggressive tone. If you are nervous of this sort of thing, simply opt for a catted exhaust. The drone added over the CBE is minimal, if you can live with the CBE portion then the full TBE will not bother you. For the sound (and the wild performance of adding a 3 inch downpipe) accept no substitutes.
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I can't wait to go stg2. I really like the sound of the perrin and a dp will only make it better

I still haven't really heard yours Micah.

The Invidia Catless Downpipe is the only downpipe I will recommend to someone.

I dig the write up! :tup:

Thanks man, way more to come. I plan on doing a write up on pretty much every part that touches my car, as well as all the tweaks I do to the car.
Great write up! I had the N1 race on my 2007 sti and freaking loved it! I now own a 2015 sti and cant wait to upgrade to the invidia N1 again!