Chrysler Repair: 2000 Chrysler 300m stuttering, bosch platinum, 2000 chrysler 300m

Question
I changed the plugs and PCV valve on 2000 Chrysler 300m.  I raced the engine
in park and it stutters and hesitates at approx. 3900 RPM's.  It also does this if I
"tap" the accelerator quickly.  I didn't notice this before I changed the plugs.  
Plugs were Bosch Platinum and I replaced them with Bosch Platinum 2 because
they were recommended and they didn't need gapping.

Answer
should have put the champion plugs in and non plat
second  no such thing as pre gapped plugs  they may come that way  but U can no predict that they are gapped correctly and if the boxes were not damaged in shipping and so on.  Put OE plugs back in  not bosh.