The Dodge Challenger Message Board

I have a 1970 Challenger RT with the 383. I just moved to Reno NV and the car has to pass a SMOG test. It passed on HC, and CO% at idle, but failed the CO% at 2500 RPM. The acceptable limit was 3.50, and the car was 5.88.......any ideas on where to start? Thanks!!

Look at the info here :

http://www.recarbco.com/technical/smog/smogspeed.html

It may be a start.

Is it not just too rich on the primary jets?

Or, after reading your other thread about low vacuum, it could be the wrong size power valve (holley) or metering rod springs (carter/edelbrock).