Afif, Mark's right. Rebuilt engines ALWAYS run hotter till the rings break in. This sometimes creates a dilemma. You need to run the engine at at least 75% power to break in the rings properly which creates more heat than running at, say, 60% power. Most updraft cooled EZ's, at least the ones that I've seen, have ramps in the lower cowl to force the air up through the two forward cylinders. The rear cylinders normally run cooler because the rear bulkhead/baffle forces the air up through them. One thing I've seen that works well is to cut holes in the top cowling, say, 1 1/2" X 5" above the hot cylinder(s). They suck the air right up through there. Maybe cut the holes then repair after the engine breaks in? It works but introduces lots of dirty air in front of the prop. Seems like Gary Hertzler did a drawing on how to do the holes with a way to keep some or most of the air attached to the cowling. I remember seeing one of those holes on Dave Ronneberg's Berkut.