1970 Challenger Failed Smog test (HELP!) • The Dodge Challenger Message Board

by **1040** » 23 Aug 2005 2:58

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!!

by **fbernard** » 23 Aug 2005 7:43

Look at the info here :

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

It may be a start.

by **dave-r** » 23 Aug 2005 7:52

Is it not just too rich on the primary jets?

by **dave-r** » 23 Aug 2005 8:00

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