An aluminum alloy for shaped castings, the alloy having the following composition ranges in weight percent: about 6.0 8.5% silicon, less than 0.4% magnesium, less than 0.1% cerium, less than 0.2% iron, copper in a range from about 0.1% to about 0.5% and/or zinc in a range from about 1% to about 4%, the alloy being particularly suited for T5 heat treatment.