just had claires rad cleaned out properly - cost $88 bux (plastic tank copper core), they take the tanks off the core and run rods through all the channels to clean out any scale/blockage

he said it was 60% blocked

she also had - split hose, thermostat that wouldnt open in a pot of boiling water, leaky drain cock and not so long ago leaky heater core.....

so yeah my hair is grey now... especially when it started over heating the brand new rebuilt motor!!!

single 12" i think would be better than two 10" (the centre hub takes up most of a ten inch anyway so actual blade area isnt huge

increasing surface area is pointless if that extra area is blocked by rad support and other things