Sorry Ed, I posted that after having had a bad day yesterday, 19 pounds per hour.
You can use any of a number of injectors in these engine with varying degrees of success. I'm assuming you're looking for replacements at less than the King's ransom prices charged by Rover vendors. If you retain the existing pressure regulator and engine management system, you should probably try to stay near the stock flow rates.
While I do not have the same experience working with the GEMS engines as I do with 14 CU(x) Lucas engines, I strongly suspect that the ability of the GEMS ECU to compensate for greatly varying rates of injector flow are limited. Published limits of control are +/-0.625 of ideal.
I have run 24 PPH injectors in a 14 CU(x) truck with less than stellar performance. The engine ran well, started great, but fuel economy was horrible. Rovacom-Lite to the rescue, I discovered the truck was running very rich and the ECU was only able to exercise limited control over injecotr pulse width and this control was not sufficient to return the stoichiometry to acceptable levels. Keep in mind I did not modify the fuel delivery system other thant he injectors. A tweaked regulator may have been of use here, but for my purposes, my reseacrh goals had been met-perhaps with results other than those desired, but my knowledge had been increased-always a good thing.
Peace,
PT