I just installed the HHO generator on my 78 Westy Bus,topped up the gas and recorded the miles. I am looking for a spot to mount a HHO generator on my 80 Westy Van, I'll let the list know, if I get any increase in milage on the bus or van. I already use Water injection on both of them, it works fin, I have been using the water injection for five years, it helps in increasing power and lowering head temp(about 03-05% increase in MPG using water, drops head temp by 75-100 degrees)I am hoping to get around 12% increase on the HHO. So if it works I should get between 22-25 MPG(I hope)..  Phil