removing smog and a/c questions

**CaminLs199** · 03-21-2011, 05:45 PM

just wondering the best and easy way to take smog and a/c off my 99 Z. and make it easier to change plugs. new to the LS1 world

. kinda..; first ls1 car

**SteveCZ28** · 03-21-2011, 07:13 PM

removing smog which is called the air and egr systems is pretty straight forward and easy...ebay sells the block off plates when you remove them for about 15 bucks...just do a search for "ls1 air egr plates" 2 10 mm bolts on the passenger side manifold takes off the egr, it has 2 15mm bolts attached to the head, and 1 10mm on the intake tube....then for the air systems its 2 10mm bolts on the passenger side manifold and 2 10mm bolts on the drivers side manifold. and pull those tubes straight out of the car.

your air hoses will look like this, they wrap from the manifolds around the back of the engine joining each other, then a t fitting runs a hose down along near the drivers side fender underneath the car to an air pump

**CaminLs199** · 03-22-2011, 04:24 PM

Originally Posted by SteveCZ28

removing smog which is called the air and egr systems is pretty straight forward and easy...ebay sells the block off plates when you remove them for about 15 bucks...just do a search for "ls1 air egr plates" 2 10 mm bolts on the passenger side manifold takes off the egr, it has 2 15mm bolts attached to the head, and 1 10mm on the intake tube....then for the air systems its 2 10mm bolts on the passenger side manifold and 2 10mm bolts on the drivers side manifold. and pull those tubes straight out of the car.

your air hoses will look like this, they wrap from the manifolds around the back of the engine joining each other, then a t fitting runs a hose down along near the drivers side fender underneath the car to an air pump

thanks man. ima do it this weekend

**SteveCZ28** · 03-22-2011, 05:37 PM

youll need a plug for the intake too, other wise youll just have a big hole sucking air...you can get the plug from gm part number 12558346 , or get a rubber expanding plug 1 3/8th inch diamter