Colder range plugs for the KA24E?

[Cone Junky]

So I am battling with some smog issues right now. My NOx is too high and I am trying to drop down combustion temps.When searching on Nico I found that there was an optional colder range plug for the SOHC in my 89 (ZFR6D-11). Unfortunately none of my vendors can find this part number.Is there another colder range plug available? Is there someplace I could find this particular plug?Any info is appreciated, thanks.

[ricebike]

the bigger picture is needed... what are the #s specifically?

guessing just from those 2, it may be your EGR valve not reducing your combustion temps?

[Cone Junky]

It's actually a long story.In a nutshell- I've dropped from 1700 ppm when I bought it, down to 987 (limit is 799).

I have cleaned EGR ports, dropped timing from 24 to 13 BTDC, ran 2 fuel injection services (Seafoam and BG), cleaned corroded injector,MAF,and ECT sensor connectors, and replaced ECT sensor.

I am making progress, in fact I have finally passed the 25 MPH test, just failed the 15 MPH test. Between the colder plugs and fixing a small exhaust leak in front of the cat, I think I should finally get it to pass.

A new cat would probably solve it, but because the PO had the cat welded in, to upgrade to the exhaust I want I would need to replace the complete system (headers,cat, cat-back) it would run about $800-900. Money which I would much rather spend on some coilovers right now.

BTW- this is on an 89 240 fastback that I bought for $700. It's become a personal challenge to get this thing to pass without any large monetary investment. So far I am under $100, including $40 spent on 2 pre-tests.

[Cone Junky]

Oops! I forget to mention- I found the plugs at the dealer. My cost was only $2.20 a peice