Texas Twin 275s - Explain please

So I missed the announcement last year about the change in this race, and I just want to make sure I understand what's going to happen - There will...

Source: http://www.motorsportforums.com/indycar/145806-texas-twin-275s-explain-please.html

Duilio Agostini Felice Agostini Giacomo Agostini Jack Ahearn Mitsuo Akamatsu