The new exhaust was fitted on the Honda-powered SF19 development car, known as 'White Tiger', with Koudai Tsukakoshi at the wheel during the first day of post-race testing at Fuji Speedway on Monday.
Toyota had already trialled its exhaust modifications in the previous test following June's Sugo round with its 'Red Tiger' driven by Hiroaki Ishiura.
Honda's offering functioned slightly differently from the one devised by Toyota, which produced the sound by way of an extra exhaust pipe for the excess gases produced by the turbo wastegate.
The Honda version instead features a single exhaust pipe that folds back on itself, with the wastegate gases being initially separated before being fed back into the main pipe at regular intervals with the main exhaust gases to produce the enhanced sound.
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Two types of exhaust were used, with a shorter version used in the morning before the longer version was fitted for the afternoon session.
"The long version sounded better," reported HRC chief engineer Yoshiyuki Ugomori, who was involved in development of the exhaust. "But I wish there was an additional step we could make to get it closer to the sound of a V8.
"At the moment, we don't have any further ideas. I think this as much as we can do at this point."
Honda's domestic motorsport boss Masahiro Saiki revealed that a preliminary test with the exhaust had taken place at Motegi's South Course to check for heat damage, and that exhausts of different length were brought to Fuji in case differing temperatures led to any unexpected changes.
However, Saiki cast doubt on the exhaust being implemented for racing owing to its increased weight, as well as its elevated cost owing to the use of Formula 1-grade heat insulation wrapping.
"The new exhaust is quite heavy, so I don't know if it will end up being used in earnest," he said. "It's clear teams wouldn't want to use something that weighs several kilograms more without bringing any performance benefits.
"So there is the question of whether the teams will accept it or not, but [Super Formula promoter] JRP wants to make the sound of the current four-cylinder engine better, and we would like to do the same."
Testing continues on Tuesday at Fuji as part of Super Formula's extensive testing plans aimed at finalising the specifications of an updated SF19 chassis slated for introduction next year.
