IndyCar officials believe they went too far with the rules package for last weekend's race at California.

While largely considered one of the most entertaining races in recent memory, Saturday's event in Fontana was blasted by several drivers for being too dangerous. At times, drivers were five wide and there was a record number of lead changes, raising concerns about contact and crashes in the open-wheel series.

IndyCar CEO Mark Miles said Wednesday that competition officials now believe the downforce levels were too aggressive for the race.

But he warned that post-race complaints from drivers are "damaging" to the series — and said the series will begin cracking down on criticism.