Ultrasonic cleaners are nice, but I have a sweet way to do it also. It involves a car battery, alligator test clips w/ wires attached, a tire valve stem w/ schrader valve removed, but must retain the valve cap, and a tiny plastic hose/straw off a can of carb cleaner or WD-40. When I'm cleaning injectors, I will make sure that they get a dose of cleaner ran through them and let set overnight night, ran through the next day, again let set overnight again for the 2nd time, and the 3rd and final cleaning begins the following day. You will need to have a spare injector connector and plenty of wire, I was lucky to have an extra junk wiring harness so I cut a connector off it, it's a little harder but you can use just wires. Look at my picture, I don't have my wire harness connector and spare wires on me at this time, so it's absent from the picture, you will have a before and after assembly. It's really neat man to have in your toolbox. After a thorough cleaning, and correct injector spray pattern is achieved, proper timing and volume efficiency can begin. A stop watch and a graduated cylinder are great pieces to begin with. If you cannot obtain these objects you can use any clear glass you can find, but just mark it for your measurements, and use a non digital clock for timing procedure. POW! (Is he saying pow) POW! POW!