The next M3 (E90/E92) will NOT have the outgoing M5's V8 engine. It will be based on the new M5's V10, with 2 cylinders chopped off. The old M5 engine was not built to withstand the 8000+ rev limit the M engineers wanted for the new car.
Fans of the original M3 will remember that car's 4 cylinder engine was essentially an M1/M535i/M635i engine with two cylinders chopped off and the cooling passages blocked off.
As for the Corvette's suspension, they are composite leafs, and they are transverse mounted. They are lighter and more durable than equivalant steel coils, reducing unsprung weight. They are more compact than steel coils, allowing for less intrusion into the chassis, which improves packaging AND lowers the center of gravity. And they have about as much in common with horse drawn carriages as an F/A-22 has with the Wright Flyer. Please don't knock something unless you know a little bit about it.
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