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Old 12-10-2012, 03:21 PM
BogiesAnnex1 BogiesAnnex1 is offline
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Originally Posted by Chevyman87 View Post
I'm reading a thread on another site and someone asks if it's ok to take off the EGR valve and solenoid. He gets mixed answers some people tell him to go ahead and do it and others tell him not to. I want to know,what do y'all think? if I'm running headers, and eliminated the A.I.R.pump, is it worth even having the EGR system?
Eliminating the AIR and EGR are more feel good activities than anything related to power gains.

All the AIR does is pump fresh air into the exhaust manifold/headers where it supplies enough air to finish the burn of fuel that didn't combust in the engine and supplies oxygen to complete the burn of carbon monoxide (a poison) to carbon dioxide. All this happens using the high temps of the exhaust to complete these reactions. Aside from some miniscule power loss running the pump from a belt and what ever aero dynamic interference the plumbing makes with the exhaust flow it does nothing to detract from engine power.

EGR is a little more complicated and its removal can burn valves and detonate but you can compensate for this when you understand what it's doing. The EGR does not operate at idle nor at high power settings. It having an effect on idle and/or WOT would only be through a failure to operate properly. It does operate at part throttle (i.e. cruise) by adding burnt exhaust back into the intake which occupies space otherwise filled with air/fuel mixture. So, yes, it would reduce power at cruise for a given throttle and timing setting by lowering the combustion temperature in the cylinder. When it is removed there is space inside the manifold of a carbureted or injected engine for more air to reach the cylinders. More air requires richening the mixture which for an emissions compliant engine whether carb or injected will not happen without an intervention to richen the mixture be that jet size increase for a carb or reprogramming the fuel map on EFI systems. If this isn't done; the mixture will be lean at cruise and burnt valves along with detonation issues are possible outcomes from this condition.

It should go without saying by this point that removal of emissions equipment is a violation of national law nearly everyplace on the planet. In the U.S. enforcement is given to the states which varies widely state to state and locale to locale within some states. Think ahead in-case your job moves you, I have a friend that moved from Texas to Maryland becuase of a job transfer, restoring his highly modified Mustang to as built emissions compliant in equipment and output proved to be a big time expensive.


Last edited by BogiesAnnex1; 12-10-2012 at 03:30 PM.
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