Sebastien Bourdais' race-winning car from last Sunday's Milwaukee IndyFest 250 has been found to have been underweight and the KVSH Racing squad fined $5000 as a result.

The infraction does not change the result of the race itself and Bourdais keeps his win, his first on an oval in nine years.

Bourdais leapt to the front of the race with a canny strategy call midway through the 250-lap race, and then blasted away from the field over the course of the remaining laps. At one point the #11 was the only car on the leap lap, such was his complete domination and superior pace over the rest of the field.

The Verizon IndyCar Series official announcement that the car had been found in breach of rule relating to minimum car weight offered no further details about the scale of the infringement or its possible impact on the car's performance or whether to what extend if any it might have contributed to Bourdais' margin of victory.

However the relatively small fine suggests that the car wasn't underweight by much and that officials deem it a technical infraction rather than one that gave any genuine advantage to Bourdais as he raced to victory last weekend.

Twice before, race-winning cars have received post-race penalties from the series but still been allowed to keep their wins. In both cases, the cars involved were from the Dale Coyne Racing team: some illegal bodywork components were found on Justin Wilson's car after his victory at Texas Motor Speedway in 2012, while Carlos Huertas' shock win at Houston last year was later followed by the announcement that his car had been in violation of rules relating to the fuel tank capacity

There were no other fines or penalties levied on drivers or teams from incidents at Milwaukee.

However, the IndyCar Series has updated the manufacturers standings with news of points deductions for both Chevrolet and Honda under rule relating to engines that fail to reach their required 2,500-mile lifespan.

In Chevrolet's case the deduction is just 20 points and relates to the engine in the car of Bourdais' KV team mate Stefano Coletti which failed midway through Sunday's race, pitching the Mon?gasque driver into retirement with less than 100 laps remaining.

For Honda, Milwaukee proved rather more costly with five failed engines, all of which incur a 20 point penalty for a total deduction of 100 points. The drivers who needed new engines at Milwaukee were Schmidt Peterson Motorsports' James Jakes, both Dale Coyne Racing drivers Tristan Vautier and Pippa Mann, and two of the Andretti Autosport cars driven by Justin Wilson and Marco Andretti,

As a result of the adjustments, Chevrolet now has 1,213 manufacturer points for the season and Honda has 899.