So when I put my LTs on and left the EGR there with the tubing just chillen in the atmoshpere, what is that doing then? The tube on the drivers side i hear sucking air in, not sure bout the pass. side. 93 LT1 car.

Exhaust gas is inert and doesn't burn like air/fuel. EGR comes on at cruise and puts a layer of inert gas in the cylinder which in turn allows less room for air/fuel mix which means a smaller flame which in turn lowers combustion chamber temps and NOx emissions. This is pretty much the reason it only comes on at cruise, and will stall a car if it opens at idle. This is how I understood it in school. It offers no performance benefit with it there or not there so long as it is functioning properly.

performance = no gain really

basically just a less cluttered engine bay/weight reduction...i removed it on my mustang because it was stuck

Found them on wikipedia proving my point that it lowers combustion tempetures. Once i find my advance systems book i can prove more with theory. Sounds like it makes no sense but its proven. Its a chemical reaction that occurs. Basicly thats Fast92RS put. Its hard to explain the science behind it.

Yet another mod myth, like taking out a cat on a relatively stock car.

No perf gain, harder to pass inspection. Lovely.

:cbrrmike: where can I buy a sticker? :cbrrmike:

Ok cool, I guess that makes sense. And ditching your cat is like 50hp!

can a car still pass with out an egr or will it automaticly fail emissions with out one ?

You'll find out, lol. For cars that get tailpipe checked, usually you will fail for high nox. I've never heard of a visual failure for egr in jersey.

hmm wonder if there is a way to put an egr in an intake that isnt made for one just so i can get this car to pass. its gona be hard enough passing the new v8 as a v6 lol

do they even actualy do visual checks ? iv never had one done or seen them do one

last time i ran through inspection in august they made me pop the hood. The guy was looking pretty thoroughly so im guessing thats what he was looking for

I've seen them manually push the EGR valve and stumble the engine to make sure it is hooked up and working.

do you mean the air pump check valves? the egr is off of the back of the intake and goes to the rear of the passenger exhaust manifold.

The egr on the back of my manifold has a hard pipe going to the pass side that bolts to Number 8 cyl. header tube and on the driver's side is a rubber tube that goes to cyl. number 1 header pipe which tees to the air pump too.

Both are just chillen open cuz my LTs.

4th gen LT1s that is.

4th gen LS1 cars- 98-00 located on the front of the intake, plug it and then get it tuned out. or even better- buy a LS6 intake and tune the egr code out

and if u bought a 01-02, there is no egr

I wonder what GM did to remove EGR on the newwer cars?
I always thought that EGR was to return a small amount of exhaust gas into the chamber to help recombust unburnt fuel, as well as lower emissions.

My 04 Avalanche has federal emissions and has no AIR or EGR. The Same 04 Avalanche with California Emissons has EGR and AIR. Im not sure what they did to add or delete it. Its gotta be in the programming somehow.

My guess is a combination of electronics and engine design. They figured how to make is pass fed regs w/less parts.

When I still had the original 305 in my car it passed inspection as I expected because I didn't mess with any of the emissions stuff. I came to find out later when I was doing a 350 swap that the EGR passages in the intake were totally plugged with carbon buildup, so basically the EGR was not working. Based on that I am thinking its possible to still pass with no EGR - at least for gen 1 SBC cars, not sure about the newer LT and LS series motors though.

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.

we need this smiley :bow:

92-93 LT1s do not have a seperate fitting in the pass. side exhaust for the EGR as the 94+ cars do. The EGR is fed via the AIR system. There is no check valve connected on the passenger side header so exhaust gasses can flow back to the port in the back of the intake, the check valve is then placed after this port.

If you hear air out of that pipe you probably have issues = vacuum or exhaust leak. you should probably delete the EGR and AIR fitting from the back on the manifold. If you leave the relay connected it should not throw a code.

http://shbox.com/1/1993_air_egr.jpg

oh got ya! thanks for clearing that up.