I live in California. My car is stock except for 2-chamber flowmaster. If I were to put a 180 deg. thermostat and a lower fan switch, would my car still pass emissions?

Akshay
89 RS T-5

 

If everything else is working correctly, you should be able to pass an emissions test with the 180°F stat. If you are concerned, you could disable the fan switch and allow the system to heat to the 215° that the factory intended while sitting in the test lane.

Your results would be interesting both ways, if you want to try the first pass with the cooler engine.