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As of this writing, Cummins has not released prices or sales structure (where to buy), but we would guess the R2.8 package will retail between $8,000 and $10,000 and will be sold through the current Cummins dealers. The biggest unknown currently is the California Air Resource Board, which is reviewing the Cummins application for an Executive Order (EO) number designating what year vehicles the engine can be used in for a legal emissions-compliant swap. Last fall, Cummins demonstrated a 25 percent reduction in CO2 emissions and lower hydrocarbon emissions too in the R2.8 as compared to the 4.0L. Cummins wants to offer the R2.8 as a 50-state-legal crate engine, even if it means only in certain older vehicles. We will have an update soon if and when CARB makes a decision.

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NOx is not mentioned.
The 25% CO2 reduction is also a sign the fuel economy will be “about” that much improved over the gasoline 4L I6