Michael Waltrip to cut back to two cars for 2014 NASCAR Sprint Cup

MWR was fined and had driver Martin Truex Jr removed from the Chase as punishment for its manipulation of the Richmond event that decided the final places in the title shootout.

NAPA, the lead sponsor on Truex's car, reacted by ending its long-term deal with the team.

Co-owners Michael Waltrip and Rob Kauffman have now announced that its efforts to find a replacement have been unsuccessful. Its #56 car will become a part-time entry and test car, with Truex free to leave the team.

Clint Bowyer and Brian Vickers, who has had to pull out of the rest of the 2013 Cup season due to blood clots, will be retained to drive Waltrip's remaining full-time Toyotas.

A team statement said that "more than 85 per cent" of personnel could be retained, with the rest released at the end of the year.

"Today was about doing what we had to do, not what we wanted to do," Kauffman said.

Waltrip insisted that the changes could ultimately make his team more competitive.

"We are confident that with two teams and a very active test team, our competitiveness will take a step forward," he said.

"We will also continue to do a great job for our partners off the track, which has always been a cultural staple for our organisation.

"Rob and I deeply appreciate everyone who has helped build MWR into a race-winning team and we are dedicated to continuing our pursuit of excellence on and off the track."