wallop
blimpchampchimpchirpclampchompclumpcrampcreepcrimpfrumpgrumpplumpprimppolyprecapskimpsloopsleepslurpstampstripstompstumpslumpswamptramptrumpuncap
zapp
peace, piece
Some six letter words with p as the second letter are opener, operas, sparse, and apiece.
Keep and kelp are four letter words starting with K and ending with P.