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Old 11-08-2008, 06:28 PM   #45
The Fixer
 
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Quote:
Originally Posted by ins0mnia24 View Post
That because Gm learned that in certain engine applications using camshafts with more valve overlap when the Intake and Exhaust valves are partially open at the same time can Lower Emission's.
Same Reason and situation with why the LS-1's in 2001 no longer used EGR Systems the LQ4 Vortec truck cam had more advance, less timing and the camshaft had more overlap which in turn created lower emission's.
Indeed. When GM got the old ZZ3 and ZZ4 certified as an emissions-legal swap in Cali, they did it without an EGR system. The cam has enough overlap to basically "self-EGR" the motor.
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'16 Go-Mango Dodge Charger R/T. It's so good to be back in a V8-powered, RWD car!

Former Toy - '88 Monte SS - had lots of mods...
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