Frequent Questions

If for the winter model an RVP of 8.7 has to be used when calculating emissions, what is the purpose of the RVP limits being 6.4 to 11 psi for conventional gasoline?

Some valid range limits must apply to conventional gasoline because even in summer months the RVP varies widely. The Complex Model contains statistically derived regression equations whose accuracy decreases dramatically when they are used outside of the valid range limits.(7/1/94)

This question and answer is posted at The original was posted in the Q&A posted on 7/1/94 which can found at" See Question ID 3857 for RFG (Taken from the first question on
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