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Need Helps With High flow cats

  • Thread starter Thread starter cedp83
  • Start date Start date Mar 12, 2010

cedp83

New Member
Aug 28, 2009
10
0
1
Duluth, GA
Mar 12, 2010
#1
  • Mar 12, 2010
  • #1
HIgh Flow Cats/Emmissions

I just got off the phone with Magnaflow, I was told I need 4 cats to keep my car legal. Do I really need to put 4 high flow cats back in my exhaust to make the car pass emmisions in GA?
2 cats won't pass testing?
I'm confused. It is impossible to put 4 cats when you have LTs. I was thinking to either buy 2 high flow cats and weld them to my O/R h pipe or buy a BBK shorty h pipe with cats but then what's the point of buying it if the car is still not gonna pass. HELP!!!!, any clarification would be appreciatted.
 
B

BannonJr

Member
Aug 12, 2006
215
0
16
St.Lazare Quebec
Apr 10, 2010
#2
  • Apr 10, 2010
  • #2
Wow, never heard of that. Good luck with that one, is there even room?
 

Twista

Active Member
May 7, 2004
510
2
29
@ the z00 in chicago
Apr 10, 2010
#3
  • Apr 10, 2010
  • #3
weld some heat shield castings on .. f- that law.
 

COBRA90GT

Mustang Master
Sep 22, 2001
6,654
0
87
HOCKEYTOWN ® , MI
Apr 10, 2010
#4
  • Apr 10, 2010
  • #4
You'll have to look up GA's exhaust/sniffer laws first RE emissions before proceeding forward.

Does GA only have a sniffer test? Or do they do a visual check underneath the car for cats? Is there a seperate registration sticker for smog/emissions purposes, etc, etc...


My *guess* is that the rep told you that you would need the four cats to pass a visual check (as some states look for 4 cats underneath the car). OR perhaps the rep felt that with your specific setup, you would need the "cleansing" power of 4 cats instead of 2 to pass a sniffer test.
 

trombonedemon

Well-Known Member
Jun 25, 2009
1,962
39
59
U.S.A, U.S.A., U.S.A.!
Apr 10, 2010
#5
  • Apr 10, 2010
  • #5
If you can eliminate the burning of blowby in your combustion chamber, you could pass w/two cats.
 

94GTCoupe

10 Year Member
May 7, 2006
1,412
92
79
CA
Apr 10, 2010
#6
  • Apr 10, 2010
  • #6
not sure about your state,but in cali
you need to have the same # of cat that came from the factory,in the stock location.
we have visual aswell as sniffer.
i could pass with 2 hi flow,but fail visual
 

cedp83

New Member
Aug 28, 2009
10
0
1
Duluth, GA
May 17, 2010
#7
  • May 17, 2010
  • #7
I have never seen a tech getting under the car or even putting a mirror close to it, basically plug to the computer, check fuel cap and that's it.
 

streethorse

15 Year Member
Oct 8, 2005
1,042
6
58
Dallas Texas
May 17, 2010
#8
  • May 17, 2010
  • #8
You have 2 choices......
go with 2 cats or put the stock midpipe back on.
 

03_TrueBlue_GT

Active Member
May 5, 2010
810
41
29
Houston, Tx
May 17, 2010
#9
  • May 17, 2010
  • #9
streethorse You have 2 choices......
go with 2 cats or put the stock midpipe back on.
Click to expand...

My Thoughts exactly. I plan on saving my stock H pipe so I can just put it back in when I go to get it inspected.
 

StangSims39

Member
Apr 17, 2010
164
0
17
Farmingdale, NY
May 17, 2010
#10
  • May 17, 2010
  • #10
In ny its only the CEL on the newer cars, so as long as my car doesn't have a cel with the Pypes cats im going to get im golden, my 95 tbird needed to go on the dyno and have the exhaust measured, and it passed with 2 magnaflow cats no problem, and the car came with 3 cats originally.
 

PULMEOVR

I need a bigger E-Penis.
Sep 29, 2003
560
0
27
Ottawa, Ontario Canada
May 19, 2010
#11
  • May 19, 2010
  • #11
The 2 cats on my MAC catted Prochamber are failing, Supposedly they are Magnaflow cats. I passed emissions for a few years but it looks like the cats are shot. I forget what chemical is reading high, but I remember it was cat related. Emissions where I live are as strict as California.
 

RedDaemon

10 Year Member
Mar 31, 2005
3,470
9
108
Atlanta, GA
May 20, 2010
#12
  • May 20, 2010
  • #12
Why not call a different manufacturer of cats and see what they say? maybe 2 magnaflow cats are just simply inefficient for GA's standards....according to magnaflow
 

patman0911

Founding Member
Jun 5, 2002
2,287
0
46
Tuscaloosa, AL
May 20, 2010
#13
  • May 20, 2010
  • #13
The law says you have to have the same number of cats in the same location as originally equipped to be legal, no matter what number of cats in what locations would satisfy a sniffer. Which seems silly to me - if two cats passes a sniffer then shouldn't that satisfy the spirit of the law? It's reducing emissions by an acceptable amount, right? Anyway, Magnaflow can't tell you just slap two on there and call it a day when the law says otherwise.

In review, your options are:

-Put four on and be completely legal
-Leave your stock pipe on and be completely legal
-Put two on and hope they never look under the car
-Put two on and weld on a pair of shells and get by a quick visual inspection
-Run whatever crazy exhaust and swap the stock pipe back for inspection and hope no one takes a peek in between (has that ever happened to anyone?)
 

StangSims39

Member
Apr 17, 2010
164
0
17
Farmingdale, NY
May 20, 2010
#14
  • May 20, 2010
  • #14
patman0911 said:
The law says you have to have the same number of cats in the same location as originally equipped to be legal, no matter what number of cats in what locations would satisfy a sniffer. Which seems silly to me - if two cats passes a sniffer then shouldn't that satisfy the spirit of the law? It's reducing emissions by an acceptable amount, right? Anyway, Magnaflow can't tell you just slap two on there and call it a day when the law says otherwise.

In review, your options are:

-Put four on and be completely legal
-Leave your stock pipe on and be completely legal
-Put two on and hope they never look under the car
-Put two on and weld on a pair of shells and get by a quick visual inspection
-Run whatever crazy exhaust and swap the stock pipe back for inspection and hope no one takes a peek in between (has that ever happened to anyone?)
Click to expand...

For what state is that?
 

patman0911

Founding Member
Jun 5, 2002
2,287
0
46
Tuscaloosa, AL
May 20, 2010
#15
  • May 20, 2010
  • #15
All 50. It's federal law. Every state chooses to inspect or not in their own way but technically if you got pulled over in a state that doesn't do smog testing, you could still get ticketed and fined if they decided to look under the car and thought your emissions equipment had been tampered with.
 

StangSims39

Member
Apr 17, 2010
164
0
17
Farmingdale, NY
May 20, 2010
#16
  • May 20, 2010
  • #16
I dont think that is true, my tbird came with 3 cats, i hacked 1 off and replaced the others with high flow cats, and i always passes inspection, i looked the NYS emissions law, and it states that a visual inspection to ensure Emission Control Devices are in place, if the car was built with Catalytic Converters from the factory, no sniffer for 96+ cars only get the ODBII scan to ensure there is no MIL from the emission system, so as per the documents, as long as there are Cats its good for visual, it did not state the car had to have the exact number of cats that came with the car only if it has them installed. And as for getting a ticket, 1 cops are way too lazy to jack up and look under the car, but if there was an over zealous cop and they did that, then you can always say the cats failed and this is what the mechanic put on.
 
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