So I'm about to order some o2 extension cables, but I noticed that on my downpipe I have a o2 sensor hole, but the header does not. Am I supposed to just unplug the one that goes to the header and extend the bottom one to the downpipe? Or am I supposed to drill and tap into the header??

http://imageshack.us/photo/my-images...934800260.jpg/

^ is what I have installed. DC Sports 4-2-1 header and downpipe.

Primary will go there yes. The secondary goes after the cat

your going to either get the ex pipe or have a shop weld a new bung hole on the stock exhaust. since that is for the ex and you have a dx exhaust after the downpipe. also another extension and a o2 simulator to get rid of the cell light if you want to pass emissions and stop your car from running rich.
http://www.hondaautomotiveparts.com/...PIPE+-+MUFFLER

Why would I need to get a shop make a new hole in the exhuast? The downpipe in the pic up there has a hole already for a sensor. Did you mean put a hole in the header?

thats for the primary sensor you need a hole for the secondary sensor further back. the ex has the cat converer under the car your stock dx has the cat attached to the manifold. i don't think you want to go drilling into your dc header plus you would have to remove the header to do.

So the EX downpipe will have 2 spots for the o2 sensors?

yes the stock ex exhaust has two holes one before the cat converter your primary and one directly after the cat your secondary sensor. since the DC race header is both the header and down pipe you need to have a shop weld on a new bung hole after the down pipe and install a o2 simulator.
http://www.robearracing.com/pd-megan...or-cel-fix.cfm

Thanks! That makes a lot more sense. When I was looking at the stock ex downpipes online I never noticed a 2nd o2 sensor hole. Guess I'll just sell off this DC downpipe and get myself a stock one instead.

no you can't because the DC race header goes into the down pipe with two separate holes then the down pipe goes into 1 hence 4,2,1 the regular dc header goes into one pipe 4,1. like this.so it won't work
http://www.ebay.com/itm/DC-Sport-01-...sories&vxp=mtr
just have a shop weld on a bung hole its very cheap.

Okay... now I think I'm confused. That is the header that I have I think (and not a race header)... But the downpipe is what goes from 2-1 right? So if I get a ex downpipe to the header than all is good?

look see your down pipe it has 2 holes just like your header how are you going to bolt this on???
http://www.ebay.com/itm/JDM-Exhaust-...99c11a&vxp=mtr
just take off the down pipe bring it to an exhaust shop and have them weld on a new bung it probably only cost you 50 bucks.

Okay. So your saying a stock ex downpipe cant connect to the header I have. I have to use the one I already have and just get a new bung put in. But now I don't have a cat right? I wanted to get the ex pipe so I can be legal on the street and pass emissions. I also wanna get rid of this downpipe because it sounds pretty noisy (not sure if that's in a good way or not). So if I want to get rid of the downpipe I have to switch the header to a stock ex header? Sorry, I'm feeling like I'm missing something here.. or I'm just totally lost and stupid lol

its louder because there is no cat yes. if you want to use the ex downpipe then yes you will have to dith that setup for a ex header dc makes them also megan. or you can keep that setup have a bung made and use a o2 simulator to be able to pass emissions you can even have a aftermarket cat welded on if you wanted to.

But that's my point right there. DC makes headers for our car and I have one on... is there some different version of DC header that I'm not aware of? If not then an ex downpipe should fit straight to my DC header no?

are you sure you don't have another bung after your flex pipe because it looks like it does in your picture also this is your header here and it has two
http://www.ebay.com/itm/DC-SPORTS-CE...8a467b&vxp=mtr
if you want to be able to use a stock ex down pipeyou wouldneed this dc header notice the one hole that requiresa donut gaskit
http://www.ebay.com/itm/NEW-DC-SPORT...3e5efa&vxp=mtr

It was so dirty that I didn't even notice it was there! Brought a lamp down there and then Thanks for all the help lowlife I feel like an idiot now lol

Second, what length of o2 extension cables should I get? it seems like the 12 inch ones would be a little too short?

Sorry for the noob question, but if I wanted to get a cat, can I just take a cat to a shop and say put this on and they'll know what to do right? No sort of special location it has to be or something?

Since that seems like it's more of a problem than it would be, I'd have to get a header that looks like this right?:
http://www.ebay.com/itm/NEW-DC-SPORT...ht_4313wt_1185

Along with a ex downpipe since it has a cat already. Correct?

i would just get the o2 simulator and be done with it ive passed emissions twice already without a cat converter. but yes you could buy a universal cat and have it welded on further down but you would still need the o2 simulator because your o2 sensors are attached on the downpipe already.

Dear Members

i hope you are well, i would like to seek your opinion and suggestions upon the following matter:

I have 1999 Honda Civic A/T with D16Y5 1.6L engine.

since beginning i have been facing with the problem of poor fuel economy and did following in this regard but no use:

1. Changed spark plugs
2. Complete engine tuning incl. throttle body service
3. Oil change (LM 10W40 MoS2)
4. LM Ceratec
5. Replaced Fuel injectors
6. Wiring check

There is no O2 sensor in the car !!!
currently it is giving around 6~7 KM/L in city and around 10~11 KM/L on highways

Please help and guide me in this regards what can be done to improve the fuel economy, is there anything that i am missing

an o2 sensor!