Just Failed CA Smog. Now what?

[mike100]

Originally Posted by 5ABI VT

The hotter the combustion temps are the better it will be on emissions. ... Oh and also the catalytic converters work better when hotter too so that may be all it needs.

The cats need to be hot and the coolant up to temp (so it doesn't run rich), but hotter combustion, extra ign timing, lugging in gears at low rpm etc will spike the oxides of nitrogens thru the roof. If anything, run with a chip made to be all stock except for the part where it turns the cooling fans on at 205 degrees (instead of the factory 228 deg F). high combustion temps bad, high catalyst temps good.

Basically pinging is the ultimate NOx production condition. egr normally blows a puff of dirty air right when you crack the throttle to keep combustion temp below the threshold for nox. but of course the early cars have 11:1 compression and no egr.