The problem we have experienced with the ZZ4 is the higher viscosity oils tend to pump the lifters up and they run too much oil pressure for my taste, small blocks don't need a lot of volume or flow, as long as there is 40-50 PSI at speed you should be fine, the reason for the larger oil pans and/or an oil cooler is with smaller capacities the oil goes around quite a few times with nothing to cool it down (just gets hotter) with a larger pan and more oil the oil makes fewer trips around and takes more heat, the synthetic will help this, the added bonus of a larger pan is reduced windage (foaming) and less likely to suck the pan dry resulting in a loss of oil pressure.
In 1997 we ran a ZZ4 for 40 min. at 6100 RPM with no problems (WW jetboat), the oil temp got to about 295 degrees (guage only went to 325*) and still had 40 pounds of oil pressure, so they will take a lot, had it not been synthetic oil, I'm sure the results would have been less favorable.
I don't like addatives, especially with synthetic, if anything, run a product proven to be compatible with synthetics...
Good luck...BTW where are the pics of this badboy?
GT
