Supercars has confirmed a change to the specification of the Ford engine ahead of this week’s Beaurepaires Sydney SuperNight.

A championship spokesperson advised, “Supercars can confirm that the Ford Homologation Team requested an Engine Specification Document (ESD) change to use an 80mm throttle body.

“This has now been tested, verified, both on and off track, and is now approved for introduction for the Beaurepaires Sydney SuperNight.”

The 80mm throttle body, which replaces the 87mm unit and now brings the Ford engine into line with the Chevrolet, is understood to be a bid to calm down the rear tyres on the Mustangs, which have been prone to using up their rubber far quicker than the Camaros.

However, it may well be accompanied by a new engine map, based on testing which took place last week at Winton.

Dick Johnson Racing undertook testing on a new engine spec(s) as the Ford homologation team at Queensland Raceway in the days following the NTI Townsville 500.

Tickford Racing and Walkinshaw Andretti United then rolled out with the 80mm throttle body for their ‘VCS Test Days’ (ie standard test) at Winton in the following week.

As reported by Speedcafe, those six Mustangs collectively ran on multiple throttle translation tables (engine maps) during the day, after which WAU’s Chaz Mostert and Nick Percat expressed a level of encouragement with what he had experienced.

The introduction of a new ESD for the Fords follows that of a new aerodynamic package ahead of the NTI Townsville 500.

While indications are that the rear bodywork tweak helped address a loss of downforce when the Mustang pitched under brakes, the tyre life problem remained.

Notably, the top Ford drivers in each of the two races around the Reid Park Street Circuit, namely Saturday podium finisher Mostert and DJR’s Sunday winner Anton De Pasquale, employed three-stop strategies to achieve those results.

This weekend’s two races at Sydney Motorsport Park, a 200km affair and a 140km contest, are likely to provide a stern test for tyre life given the high-degradation nature of the Western Sydney venue.

Adding to the jeopardy, the compulsory pit stop requirement for the longer, Saturday night race has been cut to one, meaning teams must weigh up the trade-off of extra transit time versus tyre wear.

Support category action starts this Friday at ‘Eastern Creek’.