Front "Y" with no cats question?
Thread Starter
Drifting
Joined: Jan 2001
Posts: 1,970
Likes: 21
From: Denville NJ
Front "Y" with no cats question?
I'm picking up one of these for my '86 iron head. My questions are as follows:
1.) Does it have an opening for the stock oxygen sensor?
2.) Am I going to throw any codes by eliminating the pre-cats?
3.) Are there any smog issues I will need to deal with?
4.) What does "for off road use only" really mean?
I apologize for so many questions and thank you in advance for any help or advice.
1.) Does it have an opening for the stock oxygen sensor?
2.) Am I going to throw any codes by eliminating the pre-cats?
3.) Are there any smog issues I will need to deal with?
4.) What does "for off road use only" really mean?
I apologize for so many questions and thank you in advance for any help or advice.
Instructor
Joined: Oct 2002
Posts: 213
Likes: 0
From: Choudrant LA
I believe that the "for off road use only is strictly a CYA for the company because running without cats is illegal in most, if not all, states. They wouldn't want to be selling an illegal mod, so they state that it is strictly for racing (on the track) use only. As far as I know, it will not pass smog tests, but I don't know if NJ has those. When I lived in Texas, I had to have smog tests done, but in louisiana I don't. Unless you have a "friendly" inspector, you probably won't pass any inspection with or without smog tests. I have muffler eliminators on my car, but I have a friend that does inspections. As for the codes, I have no clue....
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
Originally Posted by eric_daniel
I believe that the "for off road use only is strictly a CYA for the company because running without cats is illegal in most, if not all, states. They wouldn't want to be selling an illegal mod, so they state that it is strictly for racing (on the track) use only. As far as I know, it will not pass smog tests, but I don't know if NJ has those. When I lived in Texas, I had to have smog tests done, but in louisiana I don't. Unless you have a "friendly" inspector, you probably won't pass any inspection with or without smog tests. I have muffler eliminators on my car, but I have a friend that does inspections. As for the codes, I have no clue....
Codes... none...
visual inspection? FAILED. If NJ requires them, then you are hosed.
Racer
Joined: Nov 2005
Posts: 456
Likes: 3
From: Sumner Texas
On an '86 you won't throw a code. There is only one O2 sensor. On later models, certainly beginning in '96 if not earlier, there are O2 sensors before and after the cat that monitor the temp sensor. On those cars removing a cat would CERTAINLY result in a trouble code.
On my autocross car, an 88, I have NO cats and it doesn't throw a code.
I fully expect that the Y pipe you buy with no precats indeed has a bung for the O2 sensor.
Hope this helps,
On my autocross car, an 88, I have NO cats and it doesn't throw a code.
I fully expect that the Y pipe you buy with no precats indeed has a bung for the O2 sensor.
Hope this helps,
Thread Starter
Drifting
Joined: Jan 2001
Posts: 1,970
Likes: 21
From: Denville NJ
Originally Posted by bogus
well... as for passing smog... precats won't effect the result one bit. what will effect it is the quality of the main cat.
Codes... none...
visual inspection? FAILED. If NJ requires them, then you are hosed.
Codes... none...
visual inspection? FAILED. If NJ requires them, then you are hosed.
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
Originally Posted by MBDiagMan
On an '86 you won't throw a code. There is only one O2 sensor. On later models, certainly beginning in '96 if not earlier, there are O2 sensors before and after the cat that monitor the temp sensor. On those cars removing a cat would CERTAINLY result in a trouble code.
On my autocross car, an 88, I have NO cats and it doesn't throw a code.
I fully expect that the Y pipe you buy with no precats indeed has a bung for the O2 sensor.
Hope this helps,
On my autocross car, an 88, I have NO cats and it doesn't throw a code.
I fully expect that the Y pipe you buy with no precats indeed has a bung for the O2 sensor.
Hope this helps,
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
Originally Posted by CG77VETTE
I will also be replacing the main cat with a brand new high flow converter which dumps into a Magnaflow catback system which should be smog compliant. As far as visual, would a state inspector even know that the car came with pre-cats from the factory? Thanks to all for the replies
If the sniffer passes, then does it truely matter?
In CA, they are uber-**** about these things...
oh, and get a new 3-way cat.
If it was me, and you could do it, I would get 2 bullet cats, one on each manifold, an x-pipe and true duals from there. You would pick up 25+hp, easy.
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Team Owner
Joined: Sep 2001
Posts: 62,160
Likes: 1,733
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Originally Posted by CG77VETTE
1.) Does it have an opening for the stock oxygen sensor?
2.) Am I going to throw any codes by eliminating the pre-cats?
3.) Are there any smog issues I will need to deal with?
4.) What does "for off road use only" really mean?
2. No.
3. It will pass a sniffer-only test. The main cat is the one doing most of the work.
4. It has no CARB #. You'll fail a visual and its technically illegal to alter OE smog equipment. If NJ has no visual, dont worry about it.
Racer
Joined: Nov 2005
Posts: 456
Likes: 3
From: Sumner Texas
Originally Posted by bogus
The 2 O2s on an OBDII car do not work temp, they are testing the effectivness of the cat itself.
What the two O2 sensors do is measure the temperature before and after the cat and are looking for at least 100 degrees difference. If the 100 degrees difference is present, this is taken as an indication that the cat is indeed doing its job. This is very basic and is even a question on the ASE tests.
Have a great day,
Le Mans Master
Joined: Aug 2002
Posts: 7,441
Likes: 421
From: Ventura County, CA
St. Jude Donor '05 thru '24
Originally Posted by bogus
I would expect him to know. however, the bigger question is does he care?
If the sniffer passes, then does it truely matter?
In CA, they are uber-**** about these things...
If the sniffer passes, then does it truely matter?
In CA, they are uber-**** about these things...
I couldnt even get my Borla's welded here in California last year because at the time I wasnt running precats
So they refused to work on my car As far as throwing codes..you won't.
I, at a point in time, was running no precats and a gutted cat and had no codes. The car was pretty freakin loud, cant imagine what headers and true duals sound like
Im back to stock cats now
Last edited by ElisTwoCents; Nov 27, 2005 at 03:18 PM.
Team Owner
Joined: Sep 2003
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From: Freedom is never more than one generation away from extinction.
St. Jude '03 thru '24
Originally Posted by CG77VETTE
I'm picking up one of these for my '86 iron head. My questions are as follows:
1.) Does it have an opening for the stock oxygen sensor?
2.) Am I going to throw any codes by eliminating the pre-cats?
3.) Are there any smog issues I will need to deal with?
4.) What does "for off road use only" really mean?
1.) Does it have an opening for the stock oxygen sensor?
2.) Am I going to throw any codes by eliminating the pre-cats?
3.) Are there any smog issues I will need to deal with?
4.) What does "for off road use only" really mean?
Since the precats are only effective during the first start/warmup period, their absence is not easily detectable at a smog station. Simply cut off the precat chamber shells from your old pipe and welding them onto the catless pipe. Now you'll pass visual
Thread Starter
Drifting
Joined: Jan 2001
Posts: 1,970
Likes: 21
From: Denville NJ
Originally Posted by JrRifleCoach
My 86 iron head is running a factory 85 front Y. The O2 sensor location is a perfect match. No codes. Only smog issues is you won't pass the visual inspection. As for Q3, how can it be explained any clearer? You can't drive on the streets and highways.
Since the precats are only effective during the first start/warmup period, their absence is not easily detectable at a smog station. Simply cut off the precat chamber shells from your old pipe and welding them onto the catless pipe. Now you'll pass visual
Since the precats are only effective during the first start/warmup period, their absence is not easily detectable at a smog station. Simply cut off the precat chamber shells from your old pipe and welding them onto the catless pipe. Now you'll pass visual
Team Owner
Joined: Sep 2001
Posts: 62,160
Likes: 1,733
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Originally Posted by CG77VETTE
Does this mean you don't drive on the streets or highways with your car since you are running exactly what I will be running?
i imagine he runs his car everywhere that everyone else on the forum does
if you want to pass a strict visual, dont put the thing on there, its that simple. Otherwise, dont worry about semantics.
Burning Brakes
Joined: Nov 2000
Posts: 855
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I got my front cat-less Y and main cat from Ecklers and it was advertised as 49 State Legal. The place in California I ordered from only ordered them for me because my car was still registered in TN, but I have had it smogged twice now here in CA with the cat-less Y and have not had any issues. I believe the ad stated it was only 49 State legal if used with their 3-way main cat. Hope this helps.
Team Owner
Joined: Sep 2003
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From: Freedom is never more than one generation away from extinction.
St. Jude '03 thru '24
Nope! If a sharp Smog tech does the visual 100%, you'll fail without the precats. Although using the correct main cat WILL PASS the sniffer test. We are not authorized to alter the OEM configuration.
Sad, that we can make our engines produce more power and less smog.
Oh well! I can pass a drive by sniffer now! Thats all that matters.
Sad, that we can make our engines produce more power and less smog.
Oh well! I can pass a drive by sniffer now! Thats all that matters.
Race Director
Joined: Aug 2000
Posts: 14,130
Likes: 7
Cruise-In II Veteran
Originally Posted by Rick86
I got my front cat-less Y and main cat from Ecklers and it was advertised as 49 State Legal. The place in California I ordered from only ordered them for me because my car was still registered in TN, but I have had it smogged twice now here in CA with the cat-less Y and have not had any issues. I believe the ad stated it was only 49 State legal if used with their 3-way main cat. Hope this helps.
Good Luck!
