Don't know why it's taking me that long to address this issue but the low pressure products (tire cleaner, presoak, and spotfree) takes 45 seconds or more to reach the furthest bay. Currently our setup is: all diluted products sits above pump stand and all have solenoids pre-pump. wax and soap tied to pump on inlet side, tire cleaner, spotfree, presoak tied to pump on outlet side with check valves. Spotfree and presoak deliver products via booster pumps and tire cleaner uses a flowjet air pump. I am thinking to relocate all three low pressure to above each bay. Is it just a matter of moving low pressure product blocks and check valves to above bays and extend feed lines? If so, can I use poly tubing?