I was just pondering the downstream injector draw rates and it seems like 10 to 1 is about as hot as it gets. This would seem to be a very simple solution, and it would virtually eliminate the need for having a dedicated soft washing pump setup.
FWIW, the guy I buy my equipment from claims my injector is a 5 to 1 draw…
Do a bucket test. if you can finish filling a 5 gallon bucket and empty a 1 gallon jug at the same time then you do. Most washes require 0.70-1% strength SH so most guys run 10-12% so a 10-1 is just fine. 18-1 works just as well for the 8 gpm guys.
You’d have to force-feed it with a 12v pump. I think the general consensus is that it’s wildly inaccurate because of the pressure fluctuations in a 12v. If you need 3-1 then you might as well just batch mix and use the 12v to spray