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A few years ago you could find test pipes to replace your cats everywhere.
Now, there are none.
I don't want to rod out my cat because I just want a smooth pipe, of the correct diameter, to replace it, for a SANE PRICE.
Most States, like Connecticut, do not emissions test a 30 year old classic car. They are exempt.
I tore up the Internet looking for 1 for my 81 C3 couldn't find one, I even went looking for just the collectors so I could fabricate one with generic pipe that fell apart too. So I bought a cheap$150. catalytic converter (converter is leaking rotted)not sure if I will hollow out before installing
I tore up the Internet looking for 1 for my 81 C3 couldn't find one, I even went looking for just the collectors so I could fabricate one with generic pipe that fell apart too. So I bought a cheap$150. catalytic converter (converter is leaking rotted)not sure if I will hollow out before installing
Stainless steel pipe has gone through the roof. What is the diameter of the cat, 3"? After materials and time I may only want to make one.
The EPA cracked down on the manufacture of emissions defeat devices quite a while ago. Technically, if a vehicle was built with emission controls it is illegal to remove them regardless of the age or use of the vehicle. Hence the disappearance of the "test pipe."
Stainless steel pipe has gone through the roof. What is the diameter of the cat, 3"? After materials and time I may only want to make one.
Kind of hard to say the size because its a Square/Oval but I would say its 3"+
Here is the cheap cat I picked up but it said it fits a 84 but my Experience with C4 doesn't think it will because 84-86ish had a much larger bolt pattern that what I picked up.
And all after 86 had other had different styles
The EPA cracked down on the manufacture of emissions defeat devices quite a while ago. Technically, if a vehicle was built with emission controls it is illegal to remove them regardless of the age or use of the vehicle. Hence the disappearance of the "test pipe."
You're going to have to make your own.
The State of Connecticut does not inspect emissions on classic cars. Federal Law has just been changed about removing cats and other emissions equipment.
Kind of hard to say the size because its a Square/Oval but I would say its 3"+
Here is the cheap cat I picked up but it said it fits a 84 but my Experience with C4 doesn't think it will because 84-86ish had a much larger bolt pattern that what I picked up.
And all after 86 had other had different styles
I'm just going to get two new flanges and copy what I've got. I'll put my cat up for sale on ebay, and probably here.
If you are going to go that far why not just go with long tube headers? Problem solved plus you gain a few HP’s
I'll probably buy the front exhaust without the two cats that connect to the exhaust manifold.and core out the mid-cat.
I realize this will probably make my vette sound better and give me some back pressure relief. I know the restrictions of the L98, and I'm not going to sink money into it for more power.
Last edited by spaceweasel; Feb 10, 2025 at 09:32 AM.
The State of Connecticut does not inspect emissions on classic cars. Federal Law has just been changed about removing cats and other emissions equipment.
New York doesn't either, that wasn't the point.
If the feds changed the rules recently it's news to me. Anyway, since you claim the change is recent I doubt the market has had time to ramp up production of defeat devices. Especially since many companies were targeted and fined millions of dollars for making and installing them.
If the feds changed the rules recently it's news to me. Anyway, since you claim the change is recent I doubt the market has had time to ramp up production of defeat devices. Especially since many companies were targeted and fined millions of dollars for making and installing them.
This is really new. Just saw it in the news the other day.
Being I work adjacent to the EPA I haven't heard ****. Emissions testing or not is a moot point as on the federal level the equipment is required to be there. You don't get a state certification on a vehicle, you get a federally compliant emissions system. You get prosecuted for selling defeat devices regardless of a state by state basis. Now doing this on a 30 year old vehicle... no issue to the end user except inna few particular circumstances. The crack down was really aimed towards people doing deletes on brand new vehicles, diesels in particular. (I do not disagree with this as the roll coal bros are idiots and no one wants to deal with that.) However they just ended up going after everything. You do still see some parts labeled for offroad use only. That's how you get around it. Regardless of what happens, you probably won't see test pipes come back this term. Next go around the whip will be cracked again as the pendulum continues to swing back and forth.
Long story short. If you want it done right, just do it yourself. These cars sound like **** without work anyway, I'd rather have the cat on a stock one.
Being I work adjacent to the EPA I haven't heard ****. Emissions testing or not is a moot point as on the federal level the equipment is required to be there. You don't get a state certification on a vehicle, you get a federally compliant emissions system. You get prosecuted for selling defeat devices regardless of a state by state basis. Now doing this on a 30 year old vehicle... no issue to the end user except inna few particular circumstances. The crack down was really aimed towards people doing deletes on brand new vehicles, diesels in particular. (I do not disagree with this as the roll coal bros are idiots and no one wants to deal with that.) However they just ended up going after everything. You do still see some parts labeled for offroad use only. That's how you get around it. Regardless of what happens, you probably won't see test pipes come back this term. Next go around the whip will be cracked again as the pendulum continues to swing back and forth.
Long story short. If you want it done right, just do it yourself. These cars sound like **** without work anyway, I'd rather have the cat on a stock one.
Yeah, a lot of the youtubers who have channels but also have shops got hammered by the EPA. And usually about the diesel stuff just like you mentioned. JH Diesel has a video about it.
I would like to see some Federal action on California still requiring 1975 and newer vehicles being required to be smogged. There should be a rolling 30 year classification that exempts vehicles from emissions testing. Any car that is 30 years or older is a classic in most people's eyes.
Yeah, a lot of the youtubers who have channels but also have shops got hammered by the EPA. And usually about the diesel stuff just like you mentioned. JH Diesel has a video about it.
I would like to see some Federal action on California still requiring 1975 and newer vehicles being required to be smogged. There should be a rolling 30 year classification that exempts vehicles from emissions testing. Any car that is 30 years or older is a classic in most people's eyes.
It's this way in Connecticut. Like I said, the laws are being changed, as we speak. Be patient.
I'm just going to get two new flanges and copy what I've got. I'll put my cat up for sale on ebay, and probably here.
I made my own test pipe, easy just drop it down and trace out the flanges on to a piece of cardboard, you can use that to make gaskets too. You have to oval the pipe as it gets close to the flanges.
Yeah, a lot of the youtubers who have channels but also have shops got hammered by the EPA. And usually about the diesel stuff just like you mentioned. JH Diesel has a video about it.
I would like to see some Federal action on California still requiring 1975 and newer vehicles being required to be smogged. There should be a rolling 30 year classification that exempts vehicles from emissions testing. Any car that is 30 years or older is a classic in most people's eyes.
Most states are moving towards pre OBDII vehicles being exempt. At this point in time that would mean ~1995 and older. Mainly because they just want to be able to plug it in and go... you know, the bar is very low for the amount of knowledge expected of your average inspection worker. California is a unique example only because the topography does hold a lot of pollutants there. On top of that you have a disproportionately large amount of old vehicles still around there compared to elswhere. Enough to cause real smog that hasn't been seen since the mid 70s? No. I think it should move up to that 95 mark like everything else. Anything beyond that is quite literally a disposable appliance aside from a few select vehicles anyway.
My 84 as it sits has literally everything deleted. Long tubes new exhaust no cats or air pump. The only operable part of the emissions system is the EVAP for the fuel tank. And it's nice not having the garage reek of fuel vapors. So by all counts. Yes I am part of the problem lol.
Test Pipe, anybody?
