After putting 10,000 mi. on rebuilt heads,i just did a compression test and these are the results:#1=178 #2=180 #3=175 #4=185 #5=183 #6=175 #7=168 #8=183 I don't know what it should be with 175,000mi. but # 7 seems too low in comparison to the others.Is this normal wear of the rings/cylinders or are the valves not adjusted correctly? Sorry i don't know what the compression was before the heads were rebuilt.I had a blown head gasket that was leaking oil.