Ferrari is likely to adopt a double-stacked exhaust system with its 2019 Formula 1 car, judging by the first images of customer team Haas's new design.
Ferrari raised eyebrows last year when it trialled a new exhaust concept at the German Grand Prix.
Rather than having the two turbo wastegate pipes exiting at the side of the main exhaust like other teams, it experimented with mounting them both on top.
Sebastian Vettel conducted tests in practice at Hockenheim, with then team-mate Kimi Raikkonen sticking to the original version.
The exhaust tests took place at the same time the team introduced a new rear-wing design, which featured an upwardly curved leading edge to the main plane, suggesting part of the motivation for the tweak was to make use of exhaust blowing of the rear wing.
Another potential reason for mounting the exhausts of top of each other would be to allow even tighter packaging of the rear bodywork to help reduce aerodynamic drag.
Ferrari was able to adopt the exhaust arrangement because of a twin-pillar rear-wing mounting - something Haas also has.
Images of Haas's 2019 F1 car clearly show the exhausts mounted on top of each other, so it would be a surprise if Ferrari's challenger does not feature a similar concept when it is unveiled next week.
Although the benefits of exhaust blowing are minimal, teams may be more tempted to pursue this idea in 2019 as they bid to recover downforce lost as a result of new aero regulations aimed to help overtaking.
Renault was very aggressive in this area in 2018 as it angled its exhaust in a way to maximise opportunities for blowing gases over its rear wing.