I took my 81 Blazer 4 x 4 to the local smog station, and here's what I ended up with: Low Speed Emissions 15 mph HC 540 (standard 286) CO 2.07 (standard 1.64) NOx 1264 (standard 2125) High Speed Emissions 25 mph HC 501 (standard 281) CO 2.21 (standard 2.26) NOX 1179 (standard 1980) I am running a bone-stock Quadrajet with 4.5 turns, modified HEI distributor with an MSD module and coil, Bosch Platinum +4 plugs, and a Speed-Pro CS1013 camshaft, with Keith Black 120 pistons. I gassed the vehicle with Chevron 93 - the motor ran smoother, and right after the test failure, I went ot Midas to have the catalytic converter replaced after consulting with 2 smog inspectors after having another vehicle which passed. Just this evening, I have noticed that my CC was plugged because I had swapped the original 305 with a 350 in December 2001 - the 305 was an oil burner. There was evidence of a damaged catalyst brick, and from what I have done since this past Thursday, I have examined my old set of plugs, and all of them were tan/yellow in color - indicating a properly tuned motor. I have set the static timing to 8* BTDC, and currently running a 160* thermostat. I have 2 choices - either to park the vehicle for 2 years until April 2006, or drive it with an expired inspection sticker.