the run without water injection fig6 10 report the c 3 and c 4 yields versus 430 u00b0 f conversion we observed that at constant conversion water injected at the 90 vol point caused a decrease in propane and n butane yields and an increase in propylene and iso butane yields the butylene yield was unchanged fig1 reports the total db naphtha yield versus 430 u00b0 f conversion and shows that the naphtha yield is slightly higher at constant conversion when water is injected at the 90 vol point compared to the run without water injection fig1 and 13 report the light cycle gas oil lcgo and heavy cycle gas oil hcgo yields versus 430 u00b0 f conversion the lcgo hcgo split is the same for runs with and without water injection at and below 68 vol conversion however as 430 u00b0 f conversion is increased above 68 vol water injection yields slightly more lcgo and less hcgo than without water injection fig1 and 12 show that above 70 vol conversion there is a significant increase in total db naphtha plus lcgo yield with water quench compared to operation without water quench fig1 presents total db naphtha octane versus 430 u00b0 f conversion the upper curve is research octane and the lower curve motor octane there is no difference in octane at constant conversion with water quench versus operation without water quench however water quench allows higher conversion which increases the db naphtha octane without increasing the dry gas yield for example fig5 shows essentially equal dry gas yields for 68 conversion without water quench and for 71 conversion with water quench this increase in conversion corresponds to a 0 7 mon or ron increase in octane as shown in fig1 table i______________________________________inspection tests on catalyst equilibrium.