Passing without a cat

[Sal Lubrano]

Has anyone's GN passed emmissions without a cat installed? I know it will fail the visiable but how about the sniff test?

[turbojd]

I failed without it, my NoX's were always a little high, got sick of playing with it and I ordered a 3" cat, retested and it went through easy, just my experience. Took it off once I got home and installed the hollow 3" cat.

[ijames]

Some people have done it but most fail. I passed co and nox but the hc was about 25% too high, without a cat. Put it on and fast passed :-).

[3.8L V-8 eater]

Heres a story for ya.... I went to get my car tested for the first time so i could get some plates. I had bought a test pipe but didn't want to put it on until after testing. So, just to be on the safe side I turned down the fuel pressure unhooked the actuator rod and pured in some stuff called "guarenteed to pass" got it at auto zone.

Got the car tested and it passed... So I went home to pull of the cat to put on the test pipe and when I unhooked the exhaust I could see the cat was completely hollowed out. I sold the test pipe and left the converter on. Not recommending this will always work merly saying it worked for me.

[TurboDave]

Depends on where you're at, and what your State's limits are.

Kalifornia, and similar places? Probably not.

Tennessee, No sweat!

[pwr2spare]

Like TurboDave says it depends where you live, failed Clean Air test here in Toronto Ontario without cat. Passed with cat. I was told that these cars run on the rich side. There was also a recall concerning recalibrating chips to correct this situation.

[lottaboost6]

what about if you throw a couple gallons of e-85 in the tank?

[TurboDave]

e85 is hardly going to replace a cat. converter.

[boostmaster]

Passed without a cat or gutted cat plenty of times, the key is lowering your fuel pressure and making sure you have a working egr system. If the egr works you should pass with no sweat. Problem is most aftermarket chips disable the egr function as I found out the hard way this year when I switched from a Joe Lubrant chip to a Turbo Tweak chip and failed.

[GN1587]

just passed ma emission test no problem without converter

[TurboDave]

These kinds of statements are really pretty meaningless. The laws and limits of tests vary widely from state to state, and even region to region within a given state.

bootmaster: we don't even know where you're at. It just says USA. Are your tests and limits the same as those in southern CA? Probably not. See my point.
Can you tell me what your limits were?
Here's what my 86 (MSD 50's) had to meet in 2000 in CA just before we left.

at 15 mph
HC 151ppm max, ran 45ppm
CO 0.79% max, ran 0.08%
NO 1118 max, ran 5

at 25 mph
HC 101ppm max, ran 46ppm
CO 0.59% max, ran 0.09%
NO 978 max, ran 5

I'm pretty sure the limits are MUCH tighter by now.

That same year, my 87 (blue tops) had to meet the following limits.

at 15 mph
HC 135ppm max, ran 29ppm
CO 0.71% max, ran 0.01%
NO 1025 max, ran 7

at 25 mph
HC 85ppm max, ran 26ppm
CO 0.59% max, ran 0.04%
NO 885 max, ran 2

You can even see that the newer of the two had even tighter limits in the same test year.

[boostmaster]

Originally Posted by TurboDave

These kinds of statements are really pretty meaningless. The laws and limits of tests vary widely from state to state, and even region to region within a given state.

bootmaster: we don't even know where you're at. It just says USA. Are your tests and limits the same as those in southern CA? Probably not. See my point.
Can you tell me what your limits were?
Here's what my 86 (MSD 50's) had to meet in 2000 in CA just before we left.

at 15 mph
HC 151ppm max, ran 45ppm
CO 0.79% max, ran 0.08%
NO 1118 max, ran 5

at 25 mph
HC 101ppm max, ran 46ppm
CO 0.59% max, ran 0.09%
NO 978 max, ran 5

I'm pretty sure the limits are MUCH tighter by now.

That same year, my 87 (blue tops) had to meet the following limits.

at 15 mph
HC 135ppm max, ran 29ppm
CO 0.71% max, ran 0.01%
NO 1025 max, ran 7

at 25 mph
HC 85ppm max, ran 26ppm
CO 0.59% max, ran 0.04%
NO 885 max, ran 2

You can even see that the newer of the two had even tighter limits in the same test year.

Turbo dave I am in Atlanta, Ga and I can tell you next to California there are probably very few states with standards stricter than ours with over 12 million plus cars on the road in the metro area everyday. I'm sorry that I don't have my test results on hand since I don't keep them because our test results go straight to the dmv but I can tell you from experiance that I never failed a test until I switched to TT chips which disable the egr function then I failed on NOX. Thats running with 42lbers and 55lbers. I just turn the fuel pressure down to about 32psi static and run the test.

[lottaboost6]

I live west of Atlanta and passed with 009's and Quad air 93 chip with no EGR,intake manifold welded up egr valve not even bolted to the intake.They never looked underneath for the cat [it was on there}.Hell I don't even have a gas tank I have a fuel cell and I sawed the neck off an old tank and screwed it up in there and put a gas cap on it.It was priceless watching him pull the plate down and take the cap off and test it and then screw it back on,even Stevie Wonder could have seen theres no gas tank down there!!
My turd box 2.3 mustang failed no egr high nox threw 2 gal of e-85 in brought the nox down enough to pass