So why don't they put these "awesome" tunes on, from the factory?

[TENGRAM]

Thanks guys, very interesting info here. At least to a nuub like me. So basically, if you have a tune, when you go to get your inspection you're going to fail if they do a sniffer test. Which I don't think they do, as long as the check engine light is not on. Least I don't think they do, I can't remember.

I have a ridiculous amount of timing advance and I pass emissions by a huge margin.

[mdavis]

if its a 96 or newer it doesnt run sniffer test just plugs in and pulls codes and checks monitors. If no codes and monitors complete then it passes, pre 1996 has to be sniffed in emissions counties

[SMEGMA STENCH]

So if I delete a bunch of emissions stuff, is there some way that I can still pass? I guess just get brand new cats like the one member said.

[Jimbo]

So if I delete a bunch of emissions stuff, is there some way that I can still pass? I guess just get brand new cats like the one member said.

I've passed emissions sniffers with gutted cats, deleted smog pump, upped timing and an aftermarket cam, I believe its all about having a good tune that burns the fuel efficiently.

[Jimbo]

To compensate for varying qualities of fuel as well as long term condition of sensors and actuators.

I agree. I think it has a lot to do with safety margins in all types of driving situations.