California emissions vs federal emissions

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PRigs720

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Hello All,
Back in Jan 26 I bought a 2007 Yukon, 4.8 2wd SLT, 113K miles. The vehicle recently came to TN after spending it's prior years in CA. It has the CAB emissions sticker for the 4.8.
My question is, how does this differ from a similar 07 with regular EPA required emission equipment? This engine does not have AFM or VVT, the main reason i bought it. Is it worth it and cost effective deleating the CA spec equipment and converting it to what other similar vehicles are equipped with?
Thanks for any input. I sure do love this new to me ride.
 

Fless

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I believe you mean that it has CARB emissions. Your State may have laws that prevent legally changing the cats from CARB to Federal.

Generally if a State enforces CARB emissions, Federal cats won't be available to purchase. For example, here in the People's Republic of Colorado:

 

j91z28d1

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my understand is back in the 70s you had California market cars, but at some point it was more cost effective for manufactures to just make one car for all of America. what year that happened, I don't remember know, I'd guess late 80s.


so basically there's nothing on your truck that could can remove emissions related that won't set a check engine light on the dash. which is both annoying, and if you have any type of emissions testing in your country, it Will fail. because that's all they do is plug in and check for codes and I/M monitors these days


if you don't have local testing, then you can remove anything you want. it won't help much of anything thou, the cats arw a slight restriction, but the smell of a cat less car is pretty miserable. so unless you're racing. its not worth it. I don't really know of anything else emissions related you can remove to run better without doing things like aftermarket cam and having the ecm tuned. but a good tuners can still pass emissions with mild mods.
 

Joseph Garcia

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@j91z28d1 gave you good advice. If you want a little bit more out of your truck, without major mods or breaking the bank, get the motor and transmission tuned, and it will feel like a different rig. Check out a local tuner, or get a remote tune (still a custom for your specific truck) from BlackBear Performance, one of our trusted tuning vendors.
 

Doubeleive

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Hello All,
Back in Jan 26 I bought a 2007 Yukon, 4.8 2wd SLT, 113K miles. The vehicle recently came to TN after spending it's prior years in CA. It has the CAB emissions sticker for the 4.8.
My question is, how does this differ from a similar 07 with regular EPA required emission equipment? This engine does not have AFM or VVT, the main reason i bought it. Is it worth it and cost effective deleating the CA spec equipment and converting it to what other similar vehicles are equipped with?
Thanks for any input. I sure do love this new to me ride.
the only REAL difference is the cat's are c.a.r.b. certified, that being said if a existing cat fails and your state only requires it to have a federal cat (quick visual inspection) then you could potentially replace it with a aftermarket federal cat and go about your happy way. (the ecm does not know the difference, it's a straight money grab by california)
If they go balls deep and look for the carb number to match it up in the carb database then you cannot get away with that.
Otherwise there is no point in trying to change anything.
In fact if you changed the intake housing to a federal one (federal label instead of califonia), these idiots would likely never even know it was a california truck.
just keep in mind none of that is really "legal" but what no one knows wont hurt them......
 

West 1

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The only time I see cats fail is when the vehicle has tune issues and the owner keeps driving it to save money. If it is running rich, fix it, if you get misfires, Fix it. I have seen many cats with over 200K that work very well. If you get a coolant leak the coolant hitting the exhaust can also destroy the cats.

Keep it running well and enjoy it. The cats will be fine.
 

Doubeleive

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The only time I see cats fail is when the vehicle has tune issues and the owner keeps driving it to save money. If it is running rich, fix it, if you get misfires, Fix it. I have seen many cats with over 200K that work very well. If you get a coolant leak the coolant hitting the exhaust can also destroy the cats.

Keep it running well and enjoy it. The cats will be fine.
except for me, I burn thru cat's like there going out of style. Vehicle runs perfectly.
 

opfor2

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If/when your cats die you’ll be able to purchase and install the non CARB certified cats that are 50% cheaper.
That's why you need someone out of state to receive them for you and then reship them. This is what a friend of mine did and he save over $700.00 on the federal certified ones vs. CARB certified. Just saying
 

Doubeleive

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Just out of curiosity, when you 'burn thru' them, do they bother to tell you what they think the cause is,
or do they just say, 'ya need new cats' and not bother to say why?
I burn them up, it happens when you drive a vehicle like it's a F1 car
THEN what happened in my case is the regular front cat's blew so much crap out it clogged up the 3rd non-monitored cat, so had to have that hollowed out
that's what was causing this problem, was fine if you drive like gramma but try to do anything , pass someone, accelerate, etc and it just caused massive backpressure
skip to about 1:39
krr.JPG
 

mikez71

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I have 'heard' that our trucks run rich. I guess Doub is on the gas for prolonged periods, maybe loading the cats up with fuel?

Cat overtemp will inject more fuel when (calculated?) exhaust temps reach 1,652 degF or higher..

I am curious what his burned up cats look like...
 

Doubeleive

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I have 'heard' that our trucks run rich. I guess Doub is on the gas for prolonged periods, maybe loading the cats up with fuel?

Cat overtemp will inject more fuel when (calculated?) exhaust temps reach 1,652 degF or higher..

I am curious what his burned up cats look like...
they were not melted just discolored and could only see a small bit of light thru them, failed enough to throw a code.
that 3rd cat was a issue not only causing knock retard but associated heat as well on drives in warm weather and going up a hill or mountain the temp would climb beyond normal
I can see the difference now that the clog is gone, can't say if the cat's are lasting longer now or not the last set both broke apart inside within a couple weeks of each other.
time will tell.
 

j91z28d1

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I have 'heard' that our trucks run rich. I guess Doub is on the gas for prolonged periods, maybe loading the cats up with fuel?

Cat overtemp will inject more fuel when (calculated?) exhaust temps reach 1,652 degF or higher..

I am curious what his burned up cats look like...

cats live thru repeated track day use in cars all the time, but you have to make sure the tuners leaves cat over temp checked. if not, they do get hurt on fast cars driven hard. especially if boosted, over temp is the first thing a tuner will turn off during tuning, and then forget to turn back on.
 

BG1988

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Hello All,
Back in Jan 26 I bought a 2007 Yukon, 4.8 2wd SLT, 113K miles. The vehicle recently came to TN after spending it's prior years in CA. It has the CAB emissions sticker for the 4.8.
My question is, how does this differ from a similar 07 with regular EPA required emission equipment? This engine does not have AFM or VVT, the main reason i bought it. Is it worth it and cost effective deleating the CA spec equipment and converting it to what other similar vehicles are equipped with?
Thanks for any input. I sure do love this new to me ride.
check out the Calfiornia aftermarket Converter database

 

Doubeleive

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check out the Calfiornia aftermarket Converter database

don't matter which one you pick there all $600+ ap/walker/eastern are all the same company (giving the illusion of competition when there is none) and magnaflow has a illegal price set for there dealers, if you are a magnaflow dealer and sell them at a lower advertised price than what the company has set then you get blacklisted.
that's been illegal for decades but is not enforced
those valina appear to be ghost or the company went under.
 
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