“...nobody sells street cars based on how bad their four cylinder is...”
Well Suraru has been, and now with everybody going turbo four, they will too.
BMW, AUDI and Mercedes now use turbo four on their entry gas engines here in the USA.
And since turbo makes it easy for huge increase in street car power, the race cars become more relavent to street cars.
The courses can only handle so much top end speed. What does it matter how the power is made, to reach 200+ MPH?
second, i personally am death against owning a turo-street car... in fact one of the reasons i bought my Hyundai is because it didn't have one where the Cruze did, they are something else to maintain and go wrong and only make horse power at high RPM's
and BMW etc putting it on their "Entry Level" cars simply means their engine is too small
third, like i said before, heritage and tradition and esthetics still count... at least to me they do
when McLaren, Ferrari, Lamborghini etc start putting micro-motors in their cars it will because people WANT them there and not until then... and i don't see that anywhere in the future near or otherwise
give the fans, spelled ticket buyers, what they want... if they all start screaming for micro-motors THEN give it to them but don't try to force feed them something that just might kill ticket sales in the name of the Green Religion of Globull Warming
YMMV