John, as you will find, you will get hundreds of opinions on this. The motors I build all get Brad Penn or Comp Cams break-in oil. The cost is not a factor to me, so paying more for the oil I know works is fine for me and my customers. I like these two oils because it's premixed do the job it is intended for. I was just buying name brand oil and adding a bottle of additive which was working, but have since gone to dedicated oil. I can get the CompCams oil local so no need for shipping or special orders.
On your 235, if it's a stock rebuild with factor spec'ed cam, you will have little trouble and most likely could get away with a good quality standard oil. The cost of the additive in the long run is nothing, so I would use it anyway. I also leave the break-in oil in till I get a few drive miles on the engines, as the rings and cylinder walls are not broken in till they are loaded and unloaded by driving. I then change oil and filter, in your case the filter may be an option.
Cam design, valve spring pressure, and lifter type all determine the load placed on the camshaft, stock 235's have very little! And remember, the only way a camshaft lobe gets oiled is by splash off the rods and crank, so get the rpm up ( 1500-1800 rpm ) and let it break-in, then idle down and adjust. If it fires up and runs, let it go, worry about adjusting later. And the most important part is to have a quite exhaust system so you can hear whats going on. The second important item is to have a garden hose handy to cool the radiator, once you start the break-in, try not to stop. I have plumbed the garden hose direct to the water pump and didn't even use a radiator. I just kept adjusting the water flow to keep the temperature around 160-180. I had a thermometer in the upper outlet hose running out into the yard.
Joe
