I do not know much about the Exhaust Gas Recirculation system. It was brought to my attention as I was planning for my KA-T. Should I keep this (by putting a bung into my downpipe) or not, I have no idea. Any information would help.

Thanks in advance.

nah, everyone just puts a plate over where it used to be. no one makes turbo manifolds that have an EGR port for KA's.

If you hav an OBDII system, it may trigger a code. Mine did until I installed my E-Manage. And tailpipe emissions will go up. If you can do it, I'd put a bung. And you want to attach it to the downpipe, not the manifold. The high pressures in the manifold could cause issues with it.

Interesting. So do you think it is necessary to put a bung in the DP even if I am going with an e-manage system?

It's not necessary to run the EGR. If I had the time to get it to the shop, I'd probably plumb mine back in. The pipe to the EGR from the exhaust on mine is pinched and welded to bypass it. I figure by having it and putting a cat on the car, if I ever got harrassed by a cop about it, I could always argue that all the smog systems are functioning as they should. Probably less of a worry for those outside of CA. As far as the E-Manage, I don't know why it stopped lighting up the EGR code. But I'm not going to question it either since I had to reset the ECU once a week to get rid of it.

Ok, but in order to not get a check engine light I need to have both o2 sensors installed (one on downpipe and the other after CAT ideally) along with an EGR?

I put the EGR bung in the downpipe on my KA-T. I doesn't hurt performance and helps emmisions. It's also not in the way of anything. I pass the local smog sniffer test (Vancouver BC) just fine. Unless you go standalone the ECU will be expecting the richening of the mixture from the recirculation.