I have read that the stock exhaust on the 07 Civic Si is pretty good, so in order to save some cash, I've decided to keep the stock exhaust; however, I am wondering which to get first : Intake (Injen SRI) or Headers (which would be best?).

Also, would there be any boost in performance if I got new headers?

Thanks in advance.

 

*cough*you only have oneheader *cough* lol jk bro

I'm pretty sure a header will give you bigger gains than an intake, but I'm not positive. And, yes, a new header gives a pretty good performance boost for a bolt-on... that's why almosteveryone gets one. The only thing is that installing a new header can sometimes be a real b!tch... then again, you have an 07, so rust shouldn't be that bad of a problem.

 

I see... so if I get anything for my car, a header should be first?


Edit : And yikes... one header... not headers!! <--- n00b

 

And yeah its only 1 because your for 1 dont have a V block or stright line 6+ if you know waht I mean by this.

 

Yeah, I think a header would be a good first mod. Just make sure you get an intake, too... otherwise, your header won't really be performing to its potential

And don't worry about the header/headers thing. It's a common mistake, just like the idea that changing the vtec engagement point will do anything other than ruin fuel economy on a stock engine. For the record, to clear up what importcivicus said:

Inline configurations (I3, I4, some I6's) = one header

V, W, or largerinline configurations (some I6's,straight-8's) = two headers

 

Thanks for the clarification guys... but I read that the DC header wasn't street legal... is this true?

If so, what, if any, street legal header is preferable for 07 Civic Si?

Also, is the Injen SRI a good intake? I read good things about the MR technology...

 

DC race header isn't legal. the regular one is. megan racing is not legal.

injen is a great intake.

 

Ah yah... I misread... it was the race header that wasn't street legal. I think I am ready to get my parts

Thanks a lot guys!

 

Hey guys, I went to procivic.com to research the header I want, but I came across this :

Part Description:
2006 to 2007 Civic Coupe Si (4-2-1, One Piece) DC Sports Race Headers

Special Notes: Must use with the DC Sports exhaust. Using another exhaust will require some slight modification to the exhaust piping.[/align][/align]Since I want to use the stock exhaust, what kind of slight modifications do I have to make?[/align]

 

Well, I'm not sure, but from the sounds of it, the length of the header won't match up to the stock cat and you'll have to cut or extend some of the exhaust piping.