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Dead Parrot · 12-13-2016, 01:17 PM

If you have no emissions worries, remove the AIR pump. One less thing in the engine bay and that one does rob some power and causes more exhaust manifold heat. Its main purpose is to squirt air into the exhaust to burn off unburned fuel. Sometimes the timing was deliberately retarded a bit from normal to have more unburned fuel to improve the efficiency of the exhaust manifold burn. So you have the drag from the pump plus the loss of power and efficiency from the smaller timing advance.

You will need a plan to plug the AIR ports in the manifold. Chances of getting all 8 out after 38 years is pretty slim.

12-13-2016, 01:17 PM	#12
Dead Parrot Registered User Join Date: Aug 2012 Location: Oklahoma City, OK Posts: 2,509	Re: Throttle Body vs Carb Spacer If you have no emissions worries, remove the AIR pump. One less thing in the engine bay and that one does rob some power and causes more exhaust manifold heat. Its main purpose is to squirt air into the exhaust to burn off unburned fuel. Sometimes the timing was deliberately retarded a bit from normal to have more unburned fuel to improve the efficiency of the exhaust manifold burn. So you have the drag from the pump plus the loss of power and efficiency from the smaller timing advance. You will need a plan to plug the AIR ports in the manifold. Chances of getting all 8 out after 38 years is pretty slim.