As far as we understand you can keep the 454 engine on your Chevy Blazer as long as you install all the emission components for that engine as well. After the job is complete, your Chevy Blazer will need to be inspected by a California State Referee. The Referee will ensure that the job was done properly and that the new engine does not pollute. If all is well they will issue you a BAR label which will be placed on your Blazer's chassis and will indication that the vehicle is now California legal.
We highly recommend you speak directly with a State Referee before beginning any work, just to get the fine details. You can contact the referee by calling (800) 622-7733.
The California smog equipment requirements (or 49-state emission; they're both the same) for a 1978 Chevy 454 engine are as follows:
- PCV (Positive Crank Ventilation) System
- ACL (Pre-Heat Tube - This component is required on most vehicles with carburetor engines. The pre heat tube is usual a flexible metal duct attached to the engine's air filter housing on one end and an exhaust manifold cover on the other)
- AIS (also known as the Smog Pump)
- EGR (exhaust gas recirculation valve)
- EVAP system
- CAT (catalytic convertor)
