difference between catted and catless...

Vyruz Reaper · 12-12-2007, 03:04 PM

what is the difference between the catted and catless downpipes?

is it performance? legality? what about thrown codes?

btw.. i live in cali...

Zeroday · 12-12-2007, 03:13 PM

cat=catalytic converter

It's used to reduce toxic emissions form the exhaust. not having one is illegal in the US.

Zeroday · 12-12-2007, 03:14 PM

performance is obviously going to be better without it since it's an exhaust obstruction.

Terry335 · 12-12-2007, 03:18 PM

With catless you need the BMS o2 simms..

but they make more power. I'm not sure I would bother with catted downpipes, but catless seem to be worth a ton of torque and 10-15rwhp.

Vyruz Reaper · 12-12-2007, 03:21 PM

Quote:

Originally Posted by Terry335

With catless you need the BMS o2 simms..

but they make more power. I'm not sure I would bother with catted downpipes, but catless seem to be worth a ton of torque and 10-15rwhp.

right, but terry since u live in cali too... would this pass smog? is it illegal? can i get tickets, etc??

Pimp Star · 12-12-2007, 03:28 PM

It's not legal, but, what cop checks your exhaust when you get pulled over?

And, to answer your question, no, it does not pass smog.

BMW F22 · 12-12-2007, 03:36 PM

Quote:

Originally Posted by Pimp Star

It's not legal, but, what cop checks your exhaust when you get pulled over?

And, to answer your question, no, it does not pass smog.

Some/many cops are trained to spot mods that are illegal on cars, especially the ones in the Bay Area. I saw someone getting pulled over the other day in an Integra and the cop was inspecting his engine bay and such.

Vyruz Reaper · 12-12-2007, 03:39 PM

Quote:

Originally Posted by Kenny@JleviSW

Some/many cops are trained to spot mods that are illegal on cars, especially the ones in the Bay Area. I saw someone getting pulled over the other day in an Integra and the cop was inspecting his engine bay and such.

i got a ticket for illegal exhaust on my w203.. and i live in the bay area too.. haha

Pimp Star · 12-12-2007, 03:40 PM

:O

I've never seen that in San Diego.

Most of the tickets down here are BS anyway, I've seen quite a few police traps, also.

ArmyBimmerDude · 12-12-2007, 04:44 PM

I have catted DP's and from everything I've read, the difference is only 4-5whp. Plus you know.....you have a catted exhaust, so no worries about when you are pulled over. Also, no worries about throwing a CEL with catted. With catless you have to do what Terry said. If you want cats, I'm not much for cutting and welding them down the exhaust.

http://www.e90post.com/forums/showthread.php?t=74363

DrewKo · 12-12-2007, 05:12 PM

I'll be dynoing my car with UR catted DPs in about one week, so we'll know soon enough if these catted DPs are worth anything. However, Mr. 5 dynoed his car after installing the same catted DPs and the dyno said he lost power; however, he had a better 1/4 mile track time with the catted DPs.

For $850, or whatever catted DPs now cost, I'm not sure yet if they are worth it. I'll state a more affirmative opinion after the dyno and another 1/4 track run.

The catless ones, which are less expensive, seem worth the admission ticket from a performance perspective, but cause codes, fail emission inspections (which in Georgia are yearly), and are pretty damn loud. I guess in some or most states they are illegal too for nontrack driving.

Terry335 · 12-12-2007, 07:58 PM

Quote:

Originally Posted by Vyruz Reaper

right, but terry since u live in cali too... would this pass smog? is it illegal? can i get tickets, etc??

Removing any cats (front or back) is illegal and probably won't pass smog. But the good news is there is no test for the first 6 years so you could just put them back later.

Terry335 · 12-12-2007, 08:01 PM

Quote:

Originally Posted by DrewKo

The catless ones, which are less expensive, seem worth the admission ticket from a performance perspective, but cause codes, fail emission inspections (which in Georgia are yearly), and are pretty damn loud. I guess in some or most states they are illegal too for nontrack driving.

I think the big problem with catless ones if you already have your 2nd cats removed is they smell horrible. With the stock 2nd cats in place you seem to get the hp gains without the odor. With my simms they don't throw codes, but emission testing could be an issue.

From my experience if you keep the stock catback/2nd cats the sound is about as loud as stock, just sounds a little cooler as you get more turbo whine noise.

Can't wait to see how you do at the track! Those drag radial will really help if you wind up getting them. Bring the RPM up to 2000rpm and let her rip!

vfour · 12-12-2007, 08:18 PM

I see you have a convertible. You do not want to go cat less with a convertible. With the top down, the smell is very noticable.

Vyruz Reaper · 12-12-2007, 08:21 PM

Quote:

Originally Posted by Terry335

I think the big problem with catless ones if you already have your 2nd cats removed is they smell horrible. With the stock 2nd cats in place you seem to get the hp gains without the odor. With my simms they don't throw codes, but emission testing could be an issue.

From my experience if you keep the stock catback/2nd cats the sound is about as loud as stock, just sounds a little cooler as you get more turbo whine noise.

Can't wait to see how you do at the track! Those drag radial will really help if you wind up getting them. Bring the RPM up to 2000rpm and let her rip!

sooo im about to pull the trigger.... cant seem to know if i should go catted or catless....

DrewKo · 12-13-2007, 12:08 AM

Quote:

Originally Posted by Vyruz Reaper

sooo im about to pull the trigger.... cant seem to know if i should go catted or catless....

Wait about 10 ten days and I'll give you a dyno of before and after with the catted DPs...that may help you. If there is not enough gain to make them worthwhile, then catted DPs are out of the equation. I still would not put catless on my car though, since I live in GA have the emissions issue. I would stick with stock DPs and just get a catback exhaust that deletes the secondary cats.

uberschnell · 12-13-2007, 10:32 AM

The act of removing or replacing a cat with a non CARB approved cat is illegal in CA. No you won't pass emissions testing with no cats, and you may not pass CA with high flow cats.

CA smog inspections require a visual inspection including seeing the correct # of cats for the car (schematics are provided to techs by the auto manufacturers). You face hefty fines ($2000+) for missing cats, the shop that fails to catch this faces possible revocation of their license.

Most police are instructed to inspect for excessive sound from exhaust systems, not pollution. STILL, there is one catch, if a cop wants to inspect your car for illegal racing modifications, and is smart enough to look for it, new laws allow him to deem your car illegally modified for racing and impound your car. Have fun fighting that one in court.

Ultimate Racing · 12-13-2007, 10:37 AM

Quote:

Originally Posted by DrewKo

Wait about 10 ten days and I'll give you a dyno of before and after with the catted DPs...that may help you. If there is not enough gain to make them worthwhile, then catted DPs are out of the equation. I still would not put catless on my car though, since I live in GA have the emissions issue. I would stick with stock DPs and just get a catback exhaust that deletes the secondary cats.

If your only mods are our catted downpipes, you'll be very pleased with the dyno results.

Darryl

DrewKo · 12-13-2007, 10:52 AM

Quote:

Originally Posted by Ultimate Racing

If your only mods are our catted downpipes, you'll be very pleased with the dyno results.

Darryl

Cool! What if my mods include a piggy back? Tx.

billspreston · 12-13-2007, 11:43 AM

Quote:

Originally Posted by Magna3

The act of removing or replacing a cat with a non CARB approved cat is illegal in CA. No you won't pass emissions testing with no cats, and you may not pass CA with high flow cats.

CA smog inspections require a visual inspection including seeing the correct # of cats for the car (schematics are provided to techs by the auto manufacturers). You face hefty fines ($2000+) for missing cats, the shop that fails to catch this faces possible revocation of their license.

Most police are instructed to inspect for excessive sound from exhaust systems, not pollution. STILL, there is one catch, if a cop wants to inspect your car for illegal racing modifications, and is smart enough to look for it, new laws allow him to deem your car illegally modified for racing and impound your car. Have fun fighting that one in court.

Scariest post of 2007, way to slip it in there before the new year

Vyruz Reaper · 12-13-2007, 11:56 AM

Quote:

Originally Posted by DrewKo

Cool! What if my mods include a piggy back? Tx.

yes this is what i owuld love to know as well

Mr. 5 · 12-13-2007, 12:42 PM

This is why I don't have a super loud car.
I have high flow catted DPs with no secondaries, yet my mufflers are quiet enough to sound slightly moddified.
People think my car is too quiet but it's perfect for the street.

Quote:

Originally Posted by Magna3

The act of removing or replacing a cat with a non CARB approved cat is illegal in CA. No you won't pass emissions testing with no cats, and you may not pass CA with high flow cats.

CA smog inspections require a visual inspection including seeing the correct # of cats for the car (schematics are provided to techs by the auto manufacturers). You face hefty fines ($2000+) for missing cats, the shop that fails to catch this faces possible revocation of their license.

Most police are instructed to inspect for excessive sound from exhaust systems, not pollution. STILL, there is one catch, if a cop wants to inspect your car for illegal racing modifications, and is smart enough to look for it, new laws allow him to deem your car illegally modified for racing and impound your car. Have fun fighting that one in court.

12-12-2007, 03:04 PM	#1
Vyruz Reaper Reverse Homer 153 Rep 1,064 Posts Drives: ///M240i Join Date: May 2007 Location: Sunny SoCal iTrader: (6)	difference between catted and catless... what is the difference between the catted and catless downpipes? is it performance? legality? what about thrown codes? btw.. i live in cali...
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12-12-2007, 03:13 PM	#2
Zeroday Colonel 48 Rep 2,350 Posts Drives: Plymouth Volare Join Date: Aug 2006 Location: your nerves iTrader: (0)	cat=catalytic converter It's used to reduce toxic emissions form the exhaust. not having one is illegal in the US.
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12-12-2007, 03:14 PM	#3
Zeroday Colonel 48 Rep 2,350 Posts Drives: Plymouth Volare Join Date: Aug 2006 Location: your nerves iTrader: (0)	performance is obviously going to be better without it since it's an exhaust obstruction.
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12-12-2007, 03:18 PM	#4
Terry335 Banned 106 Rep 2,587 Posts Drives: 335i Join Date: Jan 2007 Location: Socal iTrader: (0)	With catless you need the BMS o2 simms.. but they make more power. I'm not sure I would bother with catted downpipes, but catless seem to be worth a ton of torque and 10-15rwhp.
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12-12-2007, 04:44 PM	#10
ArmyBimmerDude Major General 162 Rep 5,497 Posts Drives: Lola Join Date: Nov 2006 Location: Georgia iTrader: (3) Garage List 02/2007 E92 335i [0.00]	I have catted DP's and from everything I've read, the difference is only 4-5whp. Plus you know.....you have a catted exhaust, so no worries about when you are pulled over. Also, no worries about throwing a CEL with catted. With catless you have to do what Terry said. If you want cats, I'm not much for cutting and welding them down the exhaust. http://www.e90post.com/forums/showthread.php?t=74363 __________________ 2007 E92 Montego Blue 335i
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12-12-2007, 05:12 PM	#11
DrewKo Lieutenant Colonel 46 Rep 1,568 Posts Drives: 335i Montego Blue Saddle Brown Join Date: Jan 2007 Location: Atlanta, GA iTrader: (4) Garage List 2007 335i [0.00]	I'll be dynoing my car with UR catted DPs in about one week, so we'll know soon enough if these catted DPs are worth anything. However, Mr. 5 dynoed his car after installing the same catted DPs and the dyno said he lost power; however, he had a better 1/4 mile track time with the catted DPs. For $850, or whatever catted DPs now cost, I'm not sure yet if they are worth it. I'll state a more affirmative opinion after the dyno and another 1/4 track run. The catless ones, which are less expensive, seem worth the admission ticket from a performance perspective, but cause codes, fail emission inspections (which in Georgia are yearly), and are pretty damn loud. I guess in some or most states they are illegal too for nontrack driving.
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12-12-2007, 08:18 PM	#14
vfour Enlisted Member 6 Rep 48 Posts Drives: 2011.5 E93 Join Date: Jul 2007 Location: Central Ohio iTrader: (0)	I see you have a convertible. You do not want to go cat less with a convertible. With the top down, the smell is very noticable.
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12-13-2007, 10:32 AM	#17
uberschnell Brigadier General 687 Rep 4,080 Posts Drives: Wide Body 1 Join Date: Mar 2007 Location: Bay Area iTrader: (48)	The act of removing or replacing a cat with a non CARB approved cat is illegal in CA. No you won't pass emissions testing with no cats, and you may not pass CA with high flow cats. CA smog inspections require a visual inspection including seeing the correct # of cats for the car (schematics are provided to techs by the auto manufacturers). You face hefty fines ($2000+) for missing cats, the shop that fails to catch this faces possible revocation of their license. Most police are instructed to inspect for excessive sound from exhaust systems, not pollution. STILL, there is one catch, if a cop wants to inspect your car for illegal racing modifications, and is smart enough to look for it, new laws allow him to deem your car illegally modified for racing and impound your car. Have fun fighting that one in court.
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