New to forum and Honda. Have an 07 Si coupe. Thinking about header back exhaust replacement. Only after hp, not noise. Any recommendations on brand, model of replacement. How much hp increase can I expect? How much can I expect to pay? Would I be better off with cat back if all I'm after is hp? I'm so-so mechanically. Can I do it myself or should I have a pro do it? Installed a K&N cold air myself, slight performance boost, awesome sound. Any advice?

 

well for price us going to be over 450 and under 650 for a catback. Cat back is what your looking for accompanied by a test pipe to replace the cat or a high flow cat(which ever you prefer).

Since noise isnt an issue skunk 2 70mm makes the most gains meh around 7-9whp but is also the loudest. Then there buddy club and a list of others. Just remember that K20s love to breath.

you can do all this yourself, its all easy and straight forward. check out 8thcivic for dynos and other info on products.

also, look into a thermal intake mani gasket aswell as p2rs throttle body spacer(good bang for the buck parts).

sry i dont have more time to help right now. Hope this gives you a start. Biggest thing is take your time and do some searching/researching, and for the most part, in this market, you get what you pay for

 

if you get a test pipe you're gonna throw a CEL



get an apex-i ws2 catback

 

putting a test pipe on an 07 daily driver is for morons... its blatant pollution to get an extra 1hp gain over a high flow cat... i just finished a full header-back exhaust and put a magnaflow cat on a 98 and am quite happy with the quality.. i don't know how much is out there for 07's yet, but if you're including headers, cat, and cat-back, it'll be at LEAST $600, but probably $800+... i'd bet the whole thing would add 8-12hp... but i'm just guessing and someone will probably correct me anyway.

 

i figured the was the obvious. Buy some bungs/defoulers.



Yes it does pollute more.

for h/e it will be over 800 for quality. As far as numbers, go search 8thcivic for dynos

 

buddy club racing spec exhaust.../debate

 

Thanks, appreciate the info. Bought a Magnaflow cat back today. Maybe header later. Having a tough time locating a high flow cat for the new Si.

 

u wont see any gains, high flow cat doesnt do anything so dont waste your money

 

Wheres the proof?

 

that's funny ****, because i have some proof. http://www.importtuner.com/features/...val/index.html

found it in a STICKY on the forum
who would have guessed?

make sure you read page 2 also