Sorry, I did'nt mean main restrictors, but rather cam restrictors that sends more oil to the mains.
The main restrictors and oil resticted cam bearings do the same thing, that is, slow the oil down going to the top of the motor. Oil restricted push rods are also a good idea. Do yourself a favor and don't deal with Mondello, bad customer service. There are many other Olds specialists out there. I have been dealing with John or Dick at www.rocketracingperformance.com. They are familiar with Olds motors in jet boats.