cracked spark plugs around white housing

[toledo240]

I have a redtop sr20. Running off of bkr6e's. I keep on cracking the white part on the plugs and causes bad detenation. It running lean when at had it a 12psi but now im back to stock boost and i ant get the problem to go away. It sounds like my car is running off 3 cylinders or sounds real low like an sti motor or something. Give gas to pedal causes smoke out the exhaust, (more than usual)i think this is running rich. Everything ive done is check for spark, check connections. Im thinking my fuel pump went bad