http://www.frsport.com/Tial-38mm-External-Wastegate-Spring-Options-0.25-1.60-bar-3.6-23.2-psi_p_8967.html and I’m not even definite on the 30r, it was just an option. K04 seems like a waste of money to me, ive been in a 337 with one and a jetta with one…not that great.