Alpine appears unlikely to introduce the engine upgrade to overcome the problem that resulted in the early retirement of both its cars at the Le Mans 24 Hours this season.
The French manufacturer revealed at the Interlagos round of the World Endurance Championship in July that a valve issue put its two A424 LMDhs out at Le Mans in June before the six-hour mark.
Now, it has stated that the new hardware to cure the problem may not be introduced before the end of the season.
Alpine motorsport boss Bruno Famin told Autosport that it was “most likely” that the revised valves will not come on stream this year.
“It is the lead time. You need to define what you need, you need [to manufacture] the new part and then you need to validate the new part, which is quite a long process,” he explained.
Alpine is managing the engine protocols to overcome the problem in the absence of the upgrade and believes that the performance of its single-turbo 3.4-litre V6 is unaffected by the issue.
Famin’s comments at Austin were followed by the best qualifying performance by one of the A424s since the car's arrival in WEC at the start of this season.
Charles Milesi put the #35 Alpine fourth on the grid, three places better than the marque’s previous best of seventh at Spa in May.
That came despite the factory Signatech squad missing a collective test at the Circuit of The Americas in July in which the other seven manufacturers competing in WEC’s Hypercar class took part.
Explaining the absence, Famin added: “It was organised at the last minute and we had our own plans for testing and decided to stick with that plan.
“On top of that it was quite costly.”
Milesi believes that the resurfacing of parts of the 3.43-mile COTA track since the test at the end of July and different ambient conditions for race weekend meant that the disadvantage of its absence was reduced.
“If you test you always have a better start to the weekend, but the conditions were quite different and the asphalt has changed a bit,” he said.
Milesi stated that he could have put the car he shares with Ferdinand Habsburg and Paul-Loup Chatin second on the grid had he not “messed up the last sector” on his quick lap in the Hyperpole qualifying session for the fastest 10 cars in opening qualifying.
He attributed the improvement in Alpine’s qualifying form to the way the team managed the medium compound Michelin tyre.
“We had an issue in Free Practice 1 and missed a bit of running, but we kept improving from there,” he explained.
“We did a very good improvement from FP3 to qualifying and being able to put the tyre in the right window was the key for this qualifying performance.”
Milesi went on to say that he was unsure whether Alpine will be able to maintain its qualifying position in Sunday’s six-hour race at Austin.
“I don’t know if we will have the pace to stay in the top five, but we will be trying,” he said.
“Now we are in the right train and it is much easier from there than from the back of the queue.”
The #36 Alpine failed to make it into Hyperpole, Mick Schumacher ending up 13th in the A424 he shares with Nicolas Lapierre and Matthieu Vaxiviere.