The glow plugs are 10 amps each. I too had doubts about durability so I did a bench test. We are going to use the Air Injection Reactor circuit to control them. They will only be on when the coolant temp is below 160 degrees or the inlet air temp is below 80 degrees. Where I live that should not be very often. When they are mounted in the manifold they have a constant supply of fresh air for the idle air system flowing over the element. The manifold also acts as a large heat sink. A much friendlier environment than they were designed for. I simulated the situation with an aluminum tube and my air compressor. I ran them continuously for 4 hours with no issues. If long term durability becomes an problem I will try some 24 volt units.
