Two years ago I posted about making an emissions chip to fast pass Maryland's IM240 dyno test with 72 lb/hr injectors. This summer I had to get tested again, so for kicks I tried with no cat (with stock heads and working EGR). The limits and my values are HC: 3.8/1.8 gram/mile, CO: 16/30 gram/mile, and NOx: I forget but I was at about half the limit. I was impressed that I passed the CO and NOx but I failed the HC. Today I put on a new cat and passed with a reading of about 0.1 gpm for each gas, good enough that maybe 15 seconds into the test it flashed "fast pass" and I was done, just like two years ago. Just had to brag about it
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