catalytic converter

[juleshs]

my exhaust is blowing near the cat i get rid of the cat and run my exhaust without one???

[diesel smoke]

Yes, but if you have to get emissions checked, you're screwed.

[arb]

That is the question... do you have required emission tests?  If not, you'll get a little better mpg w/o the cat. If you have the tests, find out what the rules are for your car. In the US, the first "green diesel's" were IDI with a cat. The emission standards of the day (1986 ?) did not require the cat. And in Michigan when they did have testing in the Detroit area, if you failed a test on an older car, you could get the mechanic to sign-off saying it was too costly to repair, and you had your pass on the test anyway.