Audi S4 and S5 Could Receive Four-Cylinder Engines in 2014

Audi's extensive use of aluminium and other light materials in vehicle construction is set to continue with the next generation S5 Coupe. Speaking to Car and Driver, Audi's global head of product engineering Michael Dick said the 2014 S5 will lose up to 880 pounds (399kg) compared to the car we see on the streets right now.
Audi S4 and S5 Could Receive Four-Cylinder Engines in 2014 (3月13日/WorldCarFans)

ことの信憑性は ?? ですが、次のS4とS5のエンジンが4気筒になるとか?
アルミニウムをもっと多用して軽く仕上げる(399kg減)みたいですが、そこまでダウンサイジングできますかね??
技術的なことよりも購買者の考え方を変えることが出来るかどうかにかかっているだろうなぁ。

ソース元↓
http://www.caranddriver.com/reviews/hot_lists/high_performance/german_performance/2014_audi_s4_and_s5_massively_lighter_to_use_turbo_fours_car_news