Stock90Civic

So i have a '96 Civic hx and my cat is bad. I figured if I'm going to replace it I might as well go aftermarket. My cat is directly connected to the exhaust mani under the hood.

My plan is to buy a DC sport 4-1 header into universal cat with welded on flanges into a catback exhaust.

Would this work as long as the manifold, exhaust are carb legal and universal cat is obd2 compliant?

So im pretty much just making sure everything would fit like the stock exhaust, i would just essentially be moving the cat to under the car like the EX correct?

Thank you for any answers and all help,
Chris

94EG8

If it was anything but an HX i'd say go for it, however the HX uses a wideband O2 sensor, and from what I recall it really wants to be close to the engine. I'm not sure if you're going to end up with a CEL, but I highly suspect your gas mileage will decrease.

Stock90Civic

I was always told its an hx its the d16y7 engine. It really only gets around 35 city anyways and not too worried about gas. So the only problem i might have is the 02 wanting to screw with me?

GoLowDrew

My answer would normally be: Sounds like a good plan. As long as it does not trip off the O2 sensor. If it does, there are spacers that "fool" the system.

However, you are in CA. They do a visual inspection when you go in for smog, right? If they see aftermarket, you won't pass.

Check on this or if someone can confirm.

brutekiller787

not necessarily, as long as you spend the extra moolah on CARB complient and noise-regulation compliant stuff, you can still pass. just make sure you don't run rich or have an check engine lights on.

Ser1N

iTrader: (1)

in CA you are required to have a cat, very very big fine for not having one in Cali.

if a shop takes it off they could get fined around 25k? I dont know what the owner of the car gets fined, but i think it could get around 10k.

Stock90Civic

I know thats why i would be replacing the one that does not work. And as far as i knew the DC headers were carb legal?

Ser1N

iTrader: (1)

Yes they are.

GoLowDrew

FYI. This is an old list. Yes, your 96 is included, so therefore exempt.

http://arb.ca.gov/msprog/aftermkt/de...eo/D-370-3.pdf

trustdestruction

HX is d16y5 BTW
maybe you don't have an HX? or it was swapped

Targa250R

How many miles are on the car? If you have less than 150,000 miles, the cat converter is OEM Honda, and the Check Engine light is currently on with a P0420 code stored, then you will be able to get it replaced for free by Honda under the federal emissions warranty extension for '96-97 model year Hondas. They will only honor the warranty if these exact conditions are met, though. If you have 150,001 or more miles, or the converter is not original equipment, or the CEL is not on with a P0420 code stored, then they will not cover it.

Stock90Civic

Just rolled over 200,000 a couple weeks ago. The check engine light comes and goes as it pleases.

Anyone know of a decent to good carb legal exhaust that sounds good? Rather pay more for a better sound the pay less and not be able to stand it.

Thank you all for the answers,
Chris

94EG8

Came in here to say that, if that is the case i'd get a a DC header (or a stock EX manifold and downpipe) direct fit catalytic converter for an EX, and the EX intermediate pipe.

Stock90Civic

Thank you that's what i was looking for.

REDesignIT

Since your car is now exempt really you can do basically whatever as long as it retains a resemblance of the factory smog control device whether functioning or not.

So change that junk out, but like everyone said since the HX factory cat is at the exhaust manifold, you will need to lengthen the second O2 sensor wire if fitting a EX exhaust system to it. Maybe even the first one as well, as the bung is lower near the bottom of the radiator level and I think the HX is near the head on the stock manifold (height wise).

moving the sensors farther down stream will give a cooler reading at the O2 so will probably throw codes, there is a mod to fool the O2 reading to the ecu which should help if the CEL becomes too annoying.

Also even though you are exempt from test, they can still roadside check your car in California for mods and a road smog test, part of the visual inspection would be CEL's of course, so I am not sure what would happen at that point.

GoLowDrew

No, his car is not expempt from test. It's just the DC Header got the pass. They can't pick on him for having an aftermarket performance header.

Targa250R

If the car really is an HX with a manual transmission, be very careful messing around with the primary oxygen sensor. A new sensor is $480, and they're very easy to screw up.