upgrades

[mrnickleye]

Originally Posted by rnoswal

EGR- exhaust Gas Recirculation. Basically when you let off the throttle it causes and large vacuum in the intake. At the same time the exhaust has the most of its pollutant being emitted. The EGR valve, at the rear of the intake, opens and allows exhaust gasses to run back through the intake system. It doesn't help the mixture of fuel and air at this point, so less power when you get back on the gas. I just unbolted mine and filled the hole with JB Weld and put it back on. You could make a block off plate to go there instead. You also have to pinch off the tube that runs into the intake. The emissions will go up slightly so not sure if you would pass inspection. Here in Louisiana they don't seem to be concerned about that but the change is so small that in the big picture it doesn't bother me, probably to Green Peace it does though.


Russ

Sorry...incorrect info there. EGR operates under a cruise & load condition, not when letting off throttle. There is an exhaust back-pressure device mounted above the EGR to sense when to open the EGR valve. It lets exhaust gasses into the combustion mixture to cool down the 'burn' temp to help prevent NOX, which is form at the extreme temps created when the fuel is burning.

True...if the EGR is not operating, missing, blocked off, or plugged up (from carbon in the passages), the emission levels will raise (NOX will usually double on the test). But the #'s still may be low enough to pass the test. I know from my car.

With it not working/there, you can lower the NOX for the test by backing off timing to about 3*, then set back to 10-15* after.

Now...lets get back out there and 'rip em up' !!!