The Toyota GTP back when they dominated IMSA in the early 90's.............
1994: The year the Captain(a/k/a Roger Penske) absolutely dominated at the Brickyard in the month of May. Using a loophole in the USAC rules for that year's Indy 500, they brought three cars, each w/a 209ci push-rod Mercedes engine(the Mercedes-Benz 500I) that "technically" passed USAC rules(much to the chagrin of Ford-Cosworth, Chevrolet, HPD, TRD, the Indianapolis Motor Speedway, USAC, etc.,.......). Suffice it to say, they dominated the 500 w/"Little Al" Unser, Jr. winning his second 500.
USAC's response.......they closed the loophole for next year's 500 in near-record time; none of the Captain's entries qualified for the 500 the following year(1995)......
Say what you want about F1........at least they've got different manufacturers, something AOWR doesn't have(and really hasn't for years.........another Tony George legacy.
If there were ever any manufacturers who dominated AOWR over the past decade, it were the twin titans of HPD(Honda Performance Development) and TRD(Toyota Racing Development) who, w/budgets a tenth' or so of their F1 brethren were able to succeed(as opposed to their F1 counterparts.....
).