What pressure do you guys run sidedressing? This is an older unit that uses orifices where pressure increases with speed. Was going to add a few extra gallon this year so was going through the chart in the book and it says to shoot for 80-100 psi. Seems real high to me before I ran 60-80 and never liked to go a above 80. Trying to decide if I need to change orifices. Thanks.