I am worried about ours passing as well.
We have a '82 280 m/h with a 454, and an 'air pump' that has been disconnected by the PO. Last year it passed just fine, but this year Texas has the new more strict requirements. All gas powered cars & trucks have to be run on the 'dyno' type machine. I know that the heavier vehicles have a higher acceptable level of emmissions but I don't know if all original equipment emmissions gear is required to work properly or not.
If I can get by for 3 more years I don't have to worry about it. Vehicles that are more than 24 years old are exempt from the emmissions test.
'Can't never did nothin'!' - My Dad