when should i start looking at puting on a new gasket? i dont have any problems at this point. i have 87 turbo 7mgte with 148,xxx miles ct-57 turbo, intercooler piping and sperco knock off ic, 3inch down pipe with cut out. im running it at stock boost now but id like to put out 15 psi when i get my lexus mass air and 500 injectors. the only reasion im at stock boost is i am worried about blowing a head gasket. at what point do i have to have one?