Hi Ed,
Keeping the 216 is a matter of taste and purpose. Some people keep the babbit pounder engines to maintain originality. They also keep them if the truck isn't gonna be worked real hard or driven real fast. Conventional stovebolt wisdom is to swap to a full-pressure 235 if the truck is gonna be used a lot.
If your engine is running fine, no knocks or smoke, then let it roll! Baby it, change the oil often, and listen for strange sounds or a change in how it runs. Your engine should be OK when well maintained in stock form.
If my posts got you scared, I'm sorry. You and your son should be very proud to have built a 216 and have it live.
My 235 has been a problem child since 1996. It has had many "that can't possibly happen" failures. Its balancer has come loose, its broken a piston in half, burned up one crank, knocked the bearings out of another, beat the rods to h@ll and broken a main cap. I'll admit that a combination of bad machine shop work and my inexperience during assembly caused these problems.
It also didn't help that I ran the engine hard. I thought it was in excellent shape, and it wasn't. I saw the low oil pressure, the blowby, and the smoking from the back 3 cylinders. But I continued to run it, and she came apart. Typical hotrodder mistake. Duh...
Your engine should live a long time poking along to the lumber yard and going on chocolate-milkshake runs with your son.
Best of luck
Chiphead
