Gasoline Percentage needed to Reach the Nonflammable DVPE
In Table 7 we assigned a minimum design temperature of 15[degrees]C to blends made using such a summer gasoline and estimated that a minimum blend DVPE of 16kPa would be required without ethanol.
For similar blends containing ethanol we estimated that a minimum DVPE of 24kPa would be required.
Data for the winter gasoline G3 which has a DVPE of 90kPa are shown in Figure 4.
From Table 7, the minimum DVPE for non-flammable operation at -20[degrees]C is estimated to be 50kPa.
Figure 5 shows an equivalent diagram to figure 3, but instead plotted in terms of DVPE against DCN
Overall there was no correlation between T50 and driveability demerits, DVPE, or [T.
9 or higher on the correlations between T50, DVPE and TV/ L=20 for these fuels).
659 (Figures 6a-c)  and CRC 668 (Figures 7a-c) , the authors found no effect on driveability for ethanol content at any of the measured levels other than its impact on DVPE.
Most studies have found a correlation between degraded driveability and higher DVPE or lower [T.
In most of its HWD programs, the CRC measured the change in DVPE before the program started and then took samples from the vehicles at the end of the test program.
Splash-blended ethanol blends, with the consequently higher DVPE, generally showed improved driveability over the lower DVPE hydrocarbon base fuel.