Been checking up on this from time to time so figured I'd make a post on it and see what everyone thinks.
Even though cars seem to keep getting heavier and heavier the auto industry is trying new things to cut weight down.
Over about the last ten years they have been working on developing magnesium allows that can be used to replace steel and aluminium parts in car engines.
One paper I read shows a 29% weight reduction in the block assembly, oil pan, and front cover on a V6 when using magnesium alloys instead of aluminium.
It doesn't look like they have found the perfect alloy yet but I can see this trickling into the car market in several years.
First site I found was on the magnesium alloy AM-SC1 and it was used to make a three cylinder turbo diesel engine that was tested for two years and 65,000km in a Volkswagen Lupo with promising results.
Lighter motor cars for the 21st century (Solution)
and
AM-SC1, A Magnesium Alloy Developed for Automotive Powertrain Components by Advanced Magnesium Techn
This paper shows some of the testing done on the AM-HP2 magnesium alloy and it being compared against several magnesium alloys for various properties.
http://www.am-technologies.com.au/pd...plications.pdf
This last one is a presentation done last September for the Big 3 US auto makers. It has data obtained from tests with a magnesium alloy build of a
2.5L V6. Though there were some areas where the testing didn't go so well the paper seems to convey confidence that the problems can be engineered out given time.
http://www1.eere.energy.gov/vehicles...r10_powell.pdf