This is from a thread I put together on a local forum after I imported some foam lances. With a few guys asking about shampoo's and dilution ratios I figured I'd put it up here for you all :thumb: In order to simplify the dilution ratio calculations I made up 2 Excel spreadsheets that you can simply plug the numbers into and get the required dilution ratios for your foam lances. Advanced Version The first version is for those of you who would want to make accurate measurements of your pressure washers flow & siphon rates. In this version you need fill in the info in the red cells and Excel will sort out the rest This file can be downloaded here flr_advanced.xls Basic Version For those of you less inclined to spend time measuring the actual flow and siphon rates from your pressure washer, I've put together a seperate spreadsheet using the manufacturer supplied info for the flow rates. This may or may not be entirely accurate as I don't know what variance is accepted in the CE certification process. There may also be a host of other factors that affect the resulting flow rate (input water pressure, voltage, hose pipe length, etc, etc), but this should get you off to a fairly accurate start :thumb: In this version you simply pick your pressure washer, shampoo and required volume of shampoo from the drop down lists and Excel will handle the rest This version is available here flr_basic.xls :thumb: Notes One final note for all of you using pre 2007 versions of Microsoft Office. The spreadsheets use an MROUND function which is not installed by default on earlier versions of MS Excel. In order to get the spreadsheets to function correctly you may need to follow these instructions: MROUND If this function is not available, and returns the #NAME? error, install and load the Analysis ToolPak add-in. How? 1. On the Tools menu, click Add-Ins. 2. In the Add-Ins available list, select the Analysis ToolPak box, and then click OK. 3. If necessary, follow the instructions in the setup program. 4. Restart Excel to activate the Add-In.