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Do you have an intake spacer? The EGR tube supplied with BBK headers is only long enough for use if you don't have an intake spacer. I would just remove the EGR and be done with it. I removed the EGR from my Cobra and had a guy I know fab a block off plate and plug for the EGR bung on the header. I have an SCT 4-bank chip, but even when I set it on the stock tune it didn't throw a CEL.
 
Question: If one were to cap the header bung and the EGR valve itself, and then just leave the EGR valve functioning as is, would it all work? The computer would still think the EGR was working, but I'm not sure what it would do to A/F ratios and timing curves.
 
Question: If one were to cap the header bung and the EGR valve itself, and then just leave the EGR valve functioning as is, would it all work? The computer would still think the EGR was working, but I'm not sure what it would do to A/F ratios and timing curves.

I would think the a/f raito would be off due to a greater oxygen and nitrogen content in the combustion chamber compared to the carbon dioxide that could be there from egr.
 
Off a little or off alot? I mean, if you do the "half open" trick with the EGR sensor, what does that do for your A/F ratio? The computer would still think the EGR was working and adjust maps accordingly. Just keeps the CE light from coming on, correct?
 
I am an aircraft mechanic, so I just made one. Get a piece of 1/2" flexable soft copper pipe at the hardware store, about 2 feet long. This will make bending easier.

If you know a plumber you can borrow his tube flaring kit, or rent one from a plumbing store.

Put the two nuts on the soft copper pipe, back to back. Flare one end of the pipe to the correct size. bend it to the correct contour. Measure it to fit. Now flare the other end to the proper size.

This is how we do it on aircraft all day long, except we use aluminum or brass.
 
Plugging the EGR will not mess up your fueling. It's inert gas, and only functions at part load where you should be at lambda =1 (14.7:1), so you're not reaspirating raw O2 or unburned HC. I did what you mentioned about 4 years ago; I made a solid gasket to put in between the EGR valve and the intake, but left the valve plugged in so that the ECU can still see it move and not set a driver stage fault. I also threw a cap over the EGR port just for backup and to clean up the look.

The fuel mileage and part load spark timing is a legitimate concern. EGR does improve fuel economy by reducing pumping losses and the inert gas in the chamber allows you to run more spark at part load since it slows down the rate of combustion. I haven't heard any type of part load knock on my car so I'm not concerned. Detroit is a pretty flat place, so if I lived in the mountains or an area with a lot of higher load up-hill cruising I would probably be more concerned. The best way would be to us a Tweecer to just turn it off.