I just wanted to throw this up as I am bored and it may help somebody.

My car makes 313whp and 247wtq. I am running stock primaries and 1600cc secondaries. Everyone told me that I would feel the staging of the secondaries but the haltech ps1000 runs them smooth as ever. Also the stock primaries are only running at about 65-70% duty cycle so those are good to go. I have noticed that EVERYONE goes with 720cc secondaries but I recommened going to at least 1000cc's if you have a good standalone.(I know nothing about chipped ecu's). Anyway just thought that might help someone. Key points- stock primaries are good for 300whp easy and staging from 550cc to 1600cc is perfectly do-able.

 

Most EMS software can't fine-tune large injectors very well. While this makes more difference with the primaries than it does with the secondaries, it is a factor for those who want to fine-tune their engines. Staging is totally dependent on the EMS, as they tend to employ different methods of staging.