Will putting in a cat-less DP fail me at emissions testing?

drdome99 · 08-06-2004, 05:08 AM

Are there 2 cats in the STi? I'd really like to get a catless DP and catback exhaust combo. So will that still leave me with one cat? The thing is I live in Maryland where we have yearly emissions testing... so would eliminating 1 cat and leaving one still keep me under emissions levels you think? Otherwise I was just going to go with cat-back only.

***staticx313*** · 08-06-2004, 05:23 AM

A catless downpipe is that... catless... meaning you would lose all your cats. There are some downpipes that are like "half pipes" in that they replace only one cat and you MIGHT be safe with that, however Im not 100% sure. Youwill want to check with B&B or stromung or oakos or whichever of those companies that makes that "half downpipe" catless setup.

Robert~

dlowman · 08-06-2004, 05:24 AM

keeping the one cat in the midpipe should help you pass emissions. They just want to see that you have one on visual inspection typically.

drdome99 · 08-06-2004, 06:13 AM

So there is one in the down pipe and one in mid pipe? So DP + catback would leave the midpipe cat is what you are saying correct?

TreyS · 08-06-2004, 07:10 AM

It really depends on yoru state laws.

I live in Atlanta and all any 1996 and newer car needs to have to pass emissions is a valid OBDII ecu and no check engine light.

THey plug in the scan too, it talks to the ecu and looks for codes. That's it.

My Catless downpipe has a piece of cat in a little pipe where the 02 bung is and it keeps the light from coming on.

It's a godspeed dp.

Now if your state does a sniffer test and a visual test, you will fail.

TN_Sti · 08-06-2004, 07:42 AM

What about high flow cats? Here in TN they check ECU, Gas Cap pressure test, and they stick something in the tail pipe I'm guessing its a sniff test. Would high flow cats let me pass? Man I hate emissions!

Xman · 08-06-2004, 07:54 AM

a high flow cat MIGHT let you pass, it depends on how cleanly your car is tuned.

BTW drdome99 some "shorty" DP's will adapt to the midpipe and allow you to run the stock third cat and a catback, but most eliminate both cats.

I would recommend either a Godspeed DP with the little cat, or a Helix type with no cat, a high flow cat and a custom exhaust from your shop of choice. You will likely get a custom full 3" stainless setup for less than all these pricey aftermarket catback systems, and also support a local shop who just might cut you a deal on future work

***staticx313*** · 08-06-2004, 09:53 AM

Well the helix downpipe with cat showed to pass the CA emissions testing and is only $399!

If interested lmk. However I dont know if they require the factory parts... this does work though and someone posted an emission sheet showing it passed as well.

Robert~

crashsti · 08-06-2004, 11:18 AM

TN STi wrote:

Quote:

What about high flow cats? Here in TN they check ECU, Gas Cap pressure test, and they stick something in the tail pipe I'm guessing its a sniff test. Would high flow cats let me pass? Man I hate emissions!

you hate emmisions? i hate them too, but mostly when they're floating around in the air in the form of pollution. nothing worse than getting stuck in traffic behind a car that burns a quart of oil every 500 miles. seriously though, emmisions are a serious issue but often times the laws on how to test for them are created by politicians who don't know crap about what causes emmisions or what they even are. in Massachusetts its against the law to remove catalytic converters from any car that was originally equipped with them. so even if your car could theoretically pass a sniffer test, if you removed your cats they won't even test you. Automatic fail.

TreyS · 08-06-2004, 11:22 AM

Correction......

The Godspeed DP had NO CATS.

It does have an extended 02 bung with cat material in there but it does not protrude in the exhaust flow at all.

It's a really nice setup but WILL fail a visual and sniffer test.

TN_Sti · 08-06-2004, 11:34 AM

Quote:

Originally Posted by crashsti

TN STi wrote:

Quote:

What about high flow cats? Here in TN they check ECU, Gas Cap pressure test, and they stick something in the tail pipe I'm guessing its a sniff test. Would high flow cats let me pass? Man I hate emissions!

you hate emmisions? i hate them too, but mostly when they're floating around in the air in the form of pollution. nothing worse than getting stuck in traffic behind a car that burns a quart of oil every 500 miles. seriously though, emmisions are a serious issue but often times the laws on how to test for them are created by politicians who don't know crap about what causes emmisions or what they even are. in Massachusetts its against the law to remove catalytic converters from any car that was originally equipped with them. so even if your car could theoretically pass a sniffer test, if you removed your cats they won't even test you. Automatic fail.

The reason I hate emissions is because they don’t work. I got my emissions test 3 days ago in my Camaro. While I was waiting in the 3-mile long line I see a car drive by. This car was spewing black smoke everywhere. What is the point if everywhere I look there are cars that should not be driven.

crashsti · 08-06-2004, 11:47 AM

Quote:

crashsti wrote:
TN STi wrote:
Quote:

What about high flow cats? Here in TN they check ECU, Gas Cap pressure test, and they stick something in the tail pipe I'm guessing its a sniff test. Would high flow cats let me pass? Man I hate emissions!

you hate emmisions? i hate them too, but mostly when they're floating around in the air in the form of pollution. nothing worse than getting stuck in traffic behind a car that burns a quart of oil every 500 miles. seriously though, emmisions are a serious issue but often times the laws on how to test for them are created by politicians who don't know crap about what causes emmisions or what they even are. in Massachusetts its against the law to remove catalytic converters from any car that was originally equipped with them. so even if your car could theoretically pass a sniffer test, if you removed your cats they won't even test you. Automatic fail.

The reason I hate emissions is because they don’t work. I got my emissions test 3 days ago in my Camaro. While I was waiting in the 3-mile long line I see a car drive by. This car was spewing black smoke everywhere. What is the point if everywhere I look there are cars that should not be driven.

thats was my point, fortunately in some states the goverment is getting its act together and fails a vehicle for any signs of blue smoke from the exhaust. unfortunately most oil burning cars might pass an emmisions test but then after a few months it starts burning oil like crazy and the owner just does'nt care. they think "oh well, i have 9 months left to drive this pile into the ground, there's no way it'll pass next year." maybe cops should be required to stop and impound vehicles that spew smoke like a volcano. the truth is something has to be done about automobile emissions. before buying my STi i owned a 1969 Camaro, emissions exempt. then i get wind of a law that MA is going to start testing old cars as well as new ones. i have no idea what the standard was going to be, but according to the article i read all emissions equipment originally on the car when it was built would have to be intact. who the hell still has the SMOG crap on a 1969 Camaro? this was'nt my motivation for selling but its proof that the political body has no clue about cars and thier enthusiasts.

titsataki · 08-06-2004, 02:02 PM

Quote:

Originally Posted by staticx313

Well the helix downpipe with cat showed to pass the CA emissions testing and is only $399!

If interested lmk. However I dont know if they require the factory parts... this does work though and someone posted an emission sheet showing it passed as well.

Robert~

The only way it would pass CA smog it is to get a CARB approval.
It may pass the sniffer test but it will fail the visual.

I know of no downpipe that has CARB approval. Did Helix obtain a CARB exception id (CARB approval)?

cheers

Nick

Fhqwhgads · 08-06-2004, 02:08 PM

I don't think the Helix will gain CARB exemption or approval because it removes one of the cats (and I think it might change the location of the other one, although not 100% sure). I highly doubt the CA legislature will allow the removal of 1 cat because as of right now, even with the cat, the Helix is basically illegal. Of course if your state doesn't have visual you will probably be fine (and if it does have visual, you still might be fine but theoretically you should fail).

I generally agree with emissions rules. What I do not agree with is the whole visual aspect. As long as the car falls within the levels deemed appropriate, everything else should be irrelevant.

**BMGofUSMC** · 06-20-2008, 02:03 PM

I am too from MD and was about to install a Invidia V3 divorced wastegate DP on my STI with a Greddy Ti-C catback... Anyone else have this set up? Will this cause my check engine light to come on or cause me to fail emision testing?

If its gonna be this big of a problem I'll just get rid of the DP and just put the exhaust on, but damnit i wanted that DP

By the way, Maryland only requires the ECU scan and (check engine light must be off) for 1996 or newer vehicles.

08-06-2004, 05:08 AM	#1
drdome99 Spec C Club Car: '04 JBP STi Fav Mod: Whiteline Steering Bushings Location: Maryland Posts: 1,798 Join Date: Feb 2004 Trader Rating: (0)	Are there 2 cats in the STi? I'd really like to get a catless DP and catback exhaust combo. So will that still leave me with one cat? The thing is I live in Maryland where we have yearly emissions testing... so would eliminating 1 cat and leaving one still keep me under emissions levels you think? Otherwise I was just going to go with cat-back only. This ad is not endorsed by this member. Please register or login to hide this ad.

08-06-2004, 09:53 AM	#8
*staticx313* Platinum Member Car: 05 Subaru WRX STI CG Fav Mod: 3" FP20G - 403WHP/417WTQ Location: Huntsville, AL Posts: 5,279 Join Date: Aug 2003 Trader Rating: (2)	Anybody here Purchased Extra Warrantee: Why? Well the helix downpipe with cat showed to pass the CA emissions testing and is only $399! If interested lmk. However I dont know if they require the factory parts... this does work though and someone posted an emission sheet showing it passed as well. Robert~

06-20-2008, 02:03 PM	#15
BMGofUSMC Gold Member Car: Silver 05 STI Fav Mod: Invidia V3 DP with Greddy Ti-C exhaust Location: MD (and) VA Posts: 55 Join Date: May 2008 Trader Rating: (0)	Re: Will putting in a cat-less DP fail me at emissions testing? I am too from MD and was about to install a Invidia V3 divorced wastegate DP on my STI with a Greddy Ti-C catback... Anyone else have this set up? Will this cause my check engine light to come on or cause me to fail emision testing? If its gonna be this big of a problem I'll just get rid of the DP and just put the exhaust on, but damnit i wanted that DP By the way, Maryland only requires the ECU scan and (check engine light must be off) for 1996 or newer vehicles. This ad is not endorsed by this member. Please register or login to hide this ad. Last edited by BMGofUSMC : 06-20-2008 at 02:08 PM.

08-06-2004, 05:23 AM	#2
*staticx313* Platinum Member Car: 05 Subaru WRX STI CG Fav Mod: 3" FP20G - 403WHP/417WTQ Location: Huntsville, AL Posts: 5,279 Join Date: Aug 2003 Trader Rating: (2)	A catless downpipe is that... catless... meaning you would lose all your cats. There are some downpipes that are like "half pipes" in that they replace only one cat and you MIGHT be safe with that, however Im not 100% sure. Youwill want to check with B&B or stromung or oakos or whichever of those companies that makes that "half downpipe" catless setup. Robert~

08-06-2004, 05:24 AM	#3
dlowman Junior STI Driver Posts: 178 Join Date: Apr 2003 Trader Rating: (0)	keeping the one cat in the midpipe should help you pass emissions. They just want to see that you have one on visual inspection typically.

08-06-2004, 06:13 AM	#4
drdome99 Spec C Club Car: '04 JBP STi Fav Mod: Whiteline Steering Bushings Location: Maryland Posts: 1,798 Join Date: Feb 2004 Trader Rating: (0)	So there is one in the down pipe and one in mid pipe? So DP + catback would leave the midpipe cat is what you are saying correct?

08-06-2004, 07:10 AM	#5
TreyS Spec C Club Car: 04 STi Fav Mod: Track Day! Location: Atlanta Posts: 1,431 Join Date: Nov 2003 Trader Rating: (0)	It really depends on yoru state laws. I live in Atlanta and all any 1996 and newer car needs to have to pass emissions is a valid OBDII ecu and no check engine light. THey plug in the scan too, it talks to the ecu and looks for codes. That's it. My Catless downpipe has a piece of cat in a little pipe where the 02 bung is and it keeps the light from coming on. It's a godspeed dp. Now if your state does a sniffer test and a visual test, you will fail.

08-06-2004, 07:42 AM	#6
TN_Sti STI Driver Fav Mod: IT Location: Nashville Posts: 214 Join Date: Jul 2004 Trader Rating: (0)	What about high flow cats? Here in TN they check ECU, Gas Cap pressure test, and they stick something in the tail pipe I'm guessing its a sniff test. Would high flow cats let me pass? Man I hate emissions!

08-06-2004, 07:54 AM	#7
Xman S204 Racer Car: 2004 STi Fav Mod: Momo fixed back seat, harness bar and Willans 6 point harness Location: Rancho Santa Margarita, C Posts: 2,827 Join Date: Apr 2003 Trader Rating: (3)	a high flow cat MIGHT let you pass, it depends on how cleanly your car is tuned. BTW drdome99 some "shorty" DP's will adapt to the midpipe and allow you to run the stock third cat and a catback, but most eliminate both cats. I would recommend either a Godspeed DP with the little cat, or a Helix type with no cat, a high flow cat and a custom exhaust from your shop of choice. You will likely get a custom full 3" stainless setup for less than all these pricey aftermarket catback systems, and also support a local shop who just might cut you a deal on future work

08-06-2004, 11:22 AM	#10
TreyS Spec C Club Car: 04 STi Fav Mod: Track Day! Location: Atlanta Posts: 1,431 Join Date: Nov 2003 Trader Rating: (0)	Correction...... The Godspeed DP had NO CATS. It does have an extended 02 bung with cat material in there but it does not protrude in the exhaust flow at all. It's a really nice setup but WILL fail a visual and sniffer test.

08-06-2004, 02:08 PM	#14
Fhqwhgads STI Driver Posts: 285 Join Date: Sep 2003 Trader Rating: (0)	I don't think the Helix will gain CARB exemption or approval because it removes one of the cats (and I think it might change the location of the other one, although not 100% sure). I highly doubt the CA legislature will allow the removal of 1 cat because as of right now, even with the cat, the Helix is basically illegal. Of course if your state doesn't have visual you will probably be fine (and if it does have visual, you still might be fine but theoretically you should fail). I generally agree with emissions rules. What I do not agree with is the whole visual aspect. As long as the car falls within the levels deemed appropriate, everything else should be irrelevant.