Car passed emissions again, cat not needed?

[Jeremy]

First, the numbers.

It's a 25 mph roller test. RPM are required to be between 1200 and 2000. My car likely did it in second, as it was tested at 1970 rpm.

HC (PPM)

Limit 143
Mine 116

CO (%)

Limit 0.46
Mine 0.30

NOx (PPM)

Limit 1000
Mine 551

Car sat for around 45 minutes before testing due to having to do it as a walk-in (lack of planning on my part). Test results seem to indicate the AFR was good by the CO % and the catalytic converter was pretty much stone cold judging by the HC and NOx numbers. I warmed it up before getting there, but it had plently of time to cool off. Temps were in the low to mid 50s this morning. Car is running Motronic still.

Given all this, and the fact that under "Visual" it says "N/A" for my car, anybody think I could get away without the cat?

Jeremy

[russc]

Ya,
you could just pass w/o cat if you lean it out more to the point were your right on the edge of NOx.

RussC

[Pat]

It would be really tough to pass without it, but i guess its possible. I dunno why he put N/A for cat visual, too lazy to look, thought the car was too old for one??

[russc]

All E28 came with a cat(except euro imports). So the test should require a cat.

RussC

It would be really tough to pass without it, but i guess its possible. I dunno why he put N/A for cat visual, too lazy to look, thought the car was too old for one??

[Boru]

I think the "visual- N/A" means that CT doesn't do a visual inspection like CA does. Here in MA if the actual emissions are in spec they don't care if you have a garbage disposal attached to the intake. It's not like feeding the C.A.R.B. extortion machine.

The twin turbo 6er would pass MA emissions (same values as CA) without a cat. The only reason the techs would look under the hood was to see what was making the wonderful sounds.

[j9fd3s]

in CA we like the loaded dyno tests, the rotaries pass easy that way. i think even they would pass with no cat if you got the mixture and timing right.

i see no reason why you couldnt get the bimmer to pass too.