Don't you think the cars and tires and engines should be American? Isn't that what Nascar was?
Grainger and Worrall is an engineering and machining company in Telford Shropshire, England. It's near the center of England, jut west of Birmingham
They made all the engine blocks used by "Chevys and Fords" in the 2015 Daytona 500
They also make the engines for the Acura NSX, and the Aston Martin DB11, and they did the F1 engines in 2014, and the 2015 NHRA Pro-stock engines. They also make parts for the Veyron and the Mulsanne, and they make brand new heads for the Rolls Royce Merlin V12 airplane engine used in Spitfires, Mustangs, Hurricanes and the Lancaster bomber.
Sept 2015 issue of Car and Driver, page 26
FWIW, Nascar doesn't claim to be American, or Made in the USA http://www.nascar.com/en_us/news-media/articles/about-nascar.html I looked, and it doesn't.