well if you unhook the switch, the secondaries will be open all of the time. whereas they would be opening at near 4000 rpms normally.
there is no way besides mechanical means (taking off the return springs, or jamming the linkage so it stays closed), and vaccuum to keep the secondaries closed
i had my secondary controler unooked for a good 3 months after i last installed the intake...the connector got behind some stuff, and lost in the mess, therefore i missplaced it. but the car seemingly ran fine, i just didnt notice 'a boost' at 4000 rpms. and i got a code. so i checked and found my problem, and now its working great and i can feel a difference. definetly more low end TQ, there will be no difference on the top end seeing as though they are already fully open anywhere after 4k rpms... maybe 25 Ft. Lbs of Tq lost by disconecting, but my butt-dyno could be wrong...but no chance of losing 60 HP! wel on second thought, if you are destructive and hate your car, and therefore do something to keep your secondaries closed all the time, then i guess you would lose near 60 HP, maybe more...what are the secondary plates? about 1 and 3/4" diameter? well you would lose 6 times that, flowing into you engine.
just unhook the electrical connector on the driver side rear just under yet attached to the intake...beside the black cylinder with vacuum hoses in and out of it. feel for your self, no damage can be caused by doing this.