I was at 25/320s with T5s, pro flow w/o lid, UNI filter, +4 timing, 150psi,145'asl.
With the lid on, I was at 25/280.
Different riders will ride in different parts of the rpm range and require different jetting.
In my experience, FMF have generally liked a one size smaller main jet when compared to T5s.
ISO purple BHQ hat. Sent from the whoops.