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Message: [QUOTE="Power Hungry, post: 263138, member: 1375"] Tim, RPM is definitely a consideration that plays into injector delivery capacity. Without enough "recovery" time at higher RPMs, you could conceivably fire an injector before the plunger has fully returned to its initial state or even before the fuel chamber is adequately refilled. High volume 7.3L injectors frequently have the oil and fuel inlets modified so that they can actually fill properly on each injection event at higher RPMs. It wasn't the intention of the graphs to be the end-all be-all of injector rating, but to provide at least some idea of how much the actual injector flow is affected by nozzle size, ICP, and Pulsewidth. There are a number of factors that must be taken into consideration when making the decision on which injectors to purchase as well as what tuning approach is going to maximize the capabilities of the injectors. Drivability characteristics, power curve, smoke control (particularly at lower RPM), hardware limitations (HPOP, Turbo, etc.), and other minor factors play into injector selection and tuning, and adequate flow charts would help make some of those choices a little easier. Just for reference, I spoke to the individual that provided the flow rates for the injectors listed and they indicated to me that the injectors were tested at the maximum reasonable RPM that would be commensurate with the test pulsewidth. So, at 2ms pulsewidth, the injectors were tested at 5000 RPM. At 3ms pulsewidth, the injectors were tested at 4000 RPM. At 4ms pulsewidth, the injectors were tested at 3000 RPM. Given that, I think these graphs would be a fairly accurate representation of what to expect when installed in a vehicle. Of course, what is seen on a bench without the effect of cylinder pressure at the nozzle (which ideally isn't significant, but still a factor) and with a very well controlled, stable HP oil rail and fuel rail is going to be a fair bit (and sometimes considerably) different than what is seen in an actual running vehicle. There's no question about that. The whole point, though, is to provide some common point for comparison between different injectors. Much like how camshafts have a grind spec sheet and are rated at Deg. duration @ .050" lift, injectors should be similarly rated along some common test specification. As for what that specification should be... Well, I leave that up to the guys that actually build the injectors. :D [/QUOTE]