Austin WEC: Porsche leads first practice with Dumas and Webber

Dumas jumped ahead of Webber by just under a tenth of a second with 15 minutes to go with a 1m47.425s and then bettered it with a 1m47.231s aboard the #18 Porsche 919 Hybrid.

That left him nearly three tenths up on Webber's best of 1m47.514s.

Oliver Jarvis set the best Audi time to take third spot with a 1m49.027s, almost 1.8s off the pace.

The second Audi R18 e-tron quattro completed only four laps before undergoing an alternator change and ended up seventh in the times on a 1m53.471s recorded by Andre Lotterer.

Toyota took fourth and fifth spots with its pair of TS040 HYBRIDS, Sebastien Buemi's 1m51.279s putting him nine tenths clear of team-mate Mike Conway.

The KCMG squad led the way in LMP2 with a 1m57.764s lap from Nicolas Lapierre at the wheel of its ORECA-Nissan 05.

That put him seven tenths up on the 1m58.342s set by Johannes van Overbeek in the best of the Extreme Speed Motorsports Ligier-Honda JSP2s.

He was in turn just one hundredth up on the sister car in the hands of Ryan Dalziel.

James Calado set the pace in GTE Pro aboard his AF Corse Ferrari 458 Italia.

His 2m06.753s was six tenths up on Toni Vilander's best in the sister car, which stopped out on the circuit early in the session with an electronic problem.

AF was trying the same engine ECU that had failed early in the race at the Nurburgring last month to try to fully understand the problem.

Patrick Pilet was only five thousandths behind the second Ferrari in the fastest of the two Manthey Porsche 911 RSRs.

Patrick Long was fastest for the Proton Porsche team in the GTE Am class.

PRACTICE ONE TIMES: