[Shotimes] High NOX

[TBailSHO@aol.com]

I recently ran my 91' through the state of Ohio version of the semiannual 
required emission test.  All test results were well within limits with the 
exeption of the Nox which had a reading of 865 PPM against a bogey of 878.  In other 
words I made it by the skin of my teeth.  The good news is that my county 
will no longer be a tested area after the first of the year.  My concerns are if 
I am doing damage to my car, or if the ozone layer over southern Ohio will 
have a big hole in it because of me.

My research of this problem has indicated high combustion chamber 
temperatures can be a cause of this.  Some information about my car which probably isn't 
pertinent is; 88K, 60K done in two steps, top of engine at 70 thou. and front 
at 80 K.  All generally recommended parts replaced at those services except 
plug wires which are original.  I've been running regular gas for about 3 years, 
mods are very early version SHO Shop Y pipe, stock cat back with Dynamax 
super turbos, Pro-M 77 MAF.  Thats about it I guess.  The car runs like a top, 
21-22 MPG on my local commute which is a mix of freeway and city surface streets 
and high 20's on the highway.

Anyone else had to deal with this problem,  or have some ideas as to what I 
might look at? Thanks for any input.  I have been on the list for many years, 
mainly a lurker but enjoy reading over the many topics that are covered and 
have learned a lot about maintaining  my 'old friend.'

Tom Bailey
Dayton, OH