Originally Posted by Jordan Y.
You'll have a hard time tuning for anything bigger than 650's on an SAFC alone. Even 650's are pretty far out there. Big adjustments with the SAFC screw up your timing by putting you on really low load maps all the time. You're probably stuck doing it with 650's if you're going to stick with the SAFC, unless you get a keydiver chip to compensate for the bigger injectors.
I really wouldnt use an SAFC for anything over 550s but thats just me.
Id seriously contemplate DSMlink, especially with a goal of 400+ hp.