Fuel injector Swap: 325i to 528e

[Dr Inline 6 MD]

I've finished an engine rebuild for my 1987 528e. Manifold, block, transmission, ect got refinished and cleaned professionally. New plumbing, throttle body, : she looks and sounds brand new. I took some parts off of a 325i, 86' I think, and snagged the fuel injectors just in case. The 325i injectors got cleaned, tested, and when they came back in the mail I put them in my 528. I didn't realize that they were completely different than the ones my engine came with. I had idling issues and the engine sounded like it had an air/fuel line leak. We realized the injectors for the 325i had a different design: the system couldn't handle the injector's rate of flow and would idle poorly before swiftly stalling unless the throttle was being nudged to keep it breathing. 

I have the old ones in and I have no issues since I made the swap. My question though is with tuning, do we think the 325i injectors could be put back in and give a bump in power? Has anyone tried this before? Would the power difference, fuel efficiency aside, be worth the effort? I don't have any experience with dyno tuning and any feedback or comments about this proposed project would be appreciated. 

[turbodan]

The 82-87 eta uses significantly larger injectors than the 325i. The 88 eta uses the same injectors as the 325i but at a lower fuel pressure. You'll were actually running much leaner with the 325i injectors. 

Bottom line is that there is no power to be had with the injectors. Throwing an M20B25 cam in will heat it up though. 

[Dr Inline 6 MD]

Cool beans, thank you for the clarification.