KJL

I see on older Z's the EGR connects to the side of the plenum on the passenger side. On newer models that appears to not be used or at least on the cars that I have looked at including my 1995. It is entirely possible it was plugged and filled when the previous owner powder coated the intake and removed the EGR system when installing headers.

Z51JEFF

Older Zs didn't have an EGR valve. I think 93 was the first year.

KJL

So is my assumption regarding the port on my plenum being filled accurate?

Z51JEFF

If it's pre 93 I would say so but not exactly clear on that.

G8nightman

Pre 93 didn't have EGR

KJL

OK....so back to my original question, on a 1995, where does the EGR connect to?

G8nightman

To the Plenum right behind the throttle body usually people block this off when they add headers

KJL

Well crap, I guess it was blocked and covered with powder coating.... I was looking to install a small temporary line from my headers to this location to knock my NoX down to pass emissions.

Dynomite

You might have an earlier plenum (90'-92')

Differences between 90', 91' and 95' ZR-1s and Engines

KJL

Bingo!! You get a cigar.... go figure. Learn something new every day about that car. I knew the injector housings were earlier version but did not know the intake was as well......I wonder why.... The match between the injector bores and the heads were terrible. I port matched the heads to the housings last year. This is when I discovered the different IH's. The previous owner said they did not want to port the original injector housings to be safe but for some reason didn't have them anymore which I thought was odd. This individual owned an earlier model ZR1 and my guess is he had it ported for that car and for some reason when he obtain the 95, likely swapped the ported components over to the new car before selling the older which now has the 95 intake and injector housings.......this is my best guess.

BTW, passed with a little help from a "Chip", CRC cleaner and fresh gas plus a some highway time.