I have the Melling LS1 pump installed in my 402 with the high pressure spring. The 402 is using a LQ4 block which I believe has slightly different oil passageways that the LS1/6. At idle I am seeing about 50 to 52 psi. Since I am still breaking in the motor, I have only taken it up to about 4500 rpms and the oil pressure was in the mid 60s. The reason I went with the high pressure spring is that I am going to run an oil cooler and the cooler and lines will drop the pressure a little bit.