GT380 Oil Injection Questions

I'm working on priming the oil injection on my old GT380 and I've got it bled and the lines primed up. Spinning the engine on the bench there is almost no oil flow. I'm getting it to around 1800 rpm with the drill, but there isn't any vacuum. I'm wondering if vacuum is required for the system to flow, or if there should be positive flow through the system. Everything has been cleaned thoroughly, and the system worked prior to being disassembled. Any advice would be much appreciated. via /r/CafeRacers https://www.reddit.com/r/CafeRacers/comments/8igbca/gt380_oil_injection_questions/?utm_source=ifttt