Lt1 overlap and Smog vs. Ls1 overlap and Smog
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Does anyone else wonder why an lt1 can get away with running a larger cam and still pass emissions while the ls1 is limited to only -4 degrees of overlap as a rule of thumb to pass Ca smog?
For ex. Largest cam to pass ca somg (ussually) in an ls1
224/224 114 = -4 degree's of overlap.
Le2 emissions cam for lt1
224/230 112lsa = 3 degrees of overlap?
cc503 (widely known as the biggest smog friendly cam from the 'off the shelf')
224/230 112 (is it not weird that le2 and cc503 have the exact same specs???) = 3 degrees of overlap
If we look at the gm hotcams
ls1 hot cam
218/227 112 = -1.5 degree of overlap, and known to fail smog
lt4 hot cam
218/228 112 = -1 degrees of overlap, known to pass smog in lt1
Am I missing something??? Lt1's pass smog with bigger cams. So does cam lift effect smog? Also do the lobe profiles/aggressiveness have anything to do with it? Because I am not seeing how this is possible.
Isn't it weird that the more "efficient" engine pollutes more at X amount of overlap? or is it just lower emission standards for the lt1?
For ex. Largest cam to pass ca somg (ussually) in an ls1
224/224 114 = -4 degree's of overlap.
Le2 emissions cam for lt1
224/230 112lsa = 3 degrees of overlap?
cc503 (widely known as the biggest smog friendly cam from the 'off the shelf')
224/230 112 (is it not weird that le2 and cc503 have the exact same specs???) = 3 degrees of overlap
If we look at the gm hotcams
ls1 hot cam
218/227 112 = -1.5 degree of overlap, and known to fail smog
lt4 hot cam
218/228 112 = -1 degrees of overlap, known to pass smog in lt1
Am I missing something??? Lt1's pass smog with bigger cams. So does cam lift effect smog? Also do the lobe profiles/aggressiveness have anything to do with it? Because I am not seeing how this is possible.
Isn't it weird that the more "efficient" engine pollutes more at X amount of overlap? or is it just lower emission standards for the lt1?