Toyota expected all teams to have sound modules by now

The regulations don't mandate them until May, but Toyota's synthetic sound module is already up and running


Toyota technical director Tom Fowler says his team already had its synthetic sound module ready before it was made mandatory by the FIA, and expected rival World Rally Championship teams to do the same.

The week before last month’s Rally México, the FIA updated the 2023 Rally1 technical regulations, mandating the need for each team to fit what it called a ‘sound module’ to its Rally1 car.

These need to produce a minimum of 80dB of sound in an open area, and must be placed two meters from both the front and rear of the car, as well as one meter above the ground.

Each competing team – Toyota, Hyundai and M-Sport Ford – must also design and implement the unit themselves, rather than the FIA supplying one common part.

Next week’s Croatia Rally is the final WRC event in which teams don’t have to run these sound modules, as the regulations come into force on May 1.

But Fowler revealed to DirtFish that Toyota had already been investigating this as early as last year, and actually had its system in place for this year’s Monte Carlo Rally.

“We’re happy with the situation,” Fowler said.

“It’s actually something at Toyota that we were investigating before it became regulated, because the feedback from our drivers in 2022 was that, particularly in populated service parks, it was sometimes difficult to make progress with the car as it’s so quiet.

“So we were anyway looking for a way to warn people that it’s coming so we can more safely move through crowded areas. And then when the FIA came and said it should be regulated we were already pretty much regulated.

“So it’s actually fitted to the car already now. We’re running it, we have been for several rallies, and if you want my slightly controversial take on it it’s that I think everyone should have it already,” Fowler added.

“And if you can’t develop a sound to come out from your car but you can develop three aero jokers in the same time period, I think your priorities are slightly skewed.”


Fowler’s comments are likely a dig at rival team Hyundai which significantly altered the front and rear aero of its i20 N Rally1 over the winter.

DirtFish understands there was some sort of gentleman’s agreement between the three teams to develop a sound module in time for January’s Monte Carlo Rally, but Toyota was the only team that followed through on that.

“We were looking at it last year because we knew it [this regulation] was coming, potentially,” M-Sport technical director Chris Williams told DirtFish.

“We actually ran one in Safari as a trial, not overly successfully, and we’ve been working on something else since then.


“But it’s only for the road sections and it’s proportional to speed, so it’s nothing big.

“Some of the teams are running it already but we have to run it from Portugal onwards.”

Asked why it was necessary for the FIA to legislate the sound modules instead of the teams all having a system ready for the Monte as supposedly agreed, Williams said: “Because we weren’t ready – it’s as simple as that.

“We didn’t have something we’re happy with and it wasn’t legislated for, so…”

Williams added that the challenge in creating the system lay in making sure it’s “robust”.

“If they [the FIA] say you have something and they say you’re going to test it, you need to make sure you’re there,” he said.

“Because if you test it and it doesn’t meet their regulation you’re up in front of the stewards.

“[We] just [need to] make it more robust, it’s as simple as that.”


M-Sport is likely to be creating a “buzzer” sound, while Hyundai is understood to be working on what team principal Cyril Abiteboul called a “signature sound” in México.

“A lot of thought has been given and we have been working with Korea [as to] what could be the signature [sound],” Abiteboul said.

“First it was important to read the regulations but thinking also in the future what we want to do to give this sort of unique signature which can be part of the brand identity of Hyundai.”

Toyota’s system is more of an amplificiation of an electric motor akin to what’s found on road cars.

“You would have heard it before,” Fowler said.


“It’s been here since Monte Carlo, whenever in EV mode we have a sound which sounds like an electric motor but it’s not.

“It’s just an amplification of what the electric motor sounds like. I don’t see why it needs to be more complicated than that.

“Every single EV and hybrid road car which is driving around today is already doing it. Most people don’t know because they think it’s the motor but it’s not.”

In a statement provided to DirtFish, FIA rally director Andrew Wheatley confirmed the topic of synthetic sound modules was first discussed when the Rally1 era began at the start of last season.


“The addition of a mandatory sound module to Rally1 cars, to increase safety for spectators and officials when the cars are moving in full EV mode in service parks or on road sections, is the result of discussions that started with the launch of the 2022 season,” Wheatley said.

“The fitting of a sound-emitting device on hybrid and electric cars is a European requirement for road cars, therefore not specific to the WRC regulations.

“Several options were considered, including solutions to be adapted from the manufacturers’ unit models available in standard cars, and a single off-the-shelf supply from the FIA.

“But the selected option was to allow manufacturers to use their own units.”