As Formula E’s new powertrains break cover, it’s clear that the chassis supplier has not been standing still either. Spark has pushed forwards the car’s evolution, with upgrades to the brakes, front suspension and driver’s seat. Here’s what you’ll find on the next generation of Formula E racing cars.
The cars run carbon brakes but these proved tricky for drivers to get on top of in the first season: the slow, twisty tracks make it hard to get the brakes up to temperature and, without shrouds, retaining heat was difficult.
“It took us quite a lot of time to find a better solution,” Spark’s technical guru Theo Gouzin told us, just after the first two days of 2015 preseason testing. “Formula E has quite special requirements. In March we showed a package which included a carbon shroud. This was really good but we pulled that package to keep costs down.”
(You can read more about what happened to that package here.)
“In June, we tested again with a new disc,” Gouzin went on. “It is a carbon disc with holes visible from the outside, but the holes don’t go all the way through the disc. That avoids the disc cooling down under rotation while keeping the weight down.”
An aluminium blanking plate has been added to improve performance without breaking the bank when raiding the spare parts shelf. New brake pad geometries complete the package.
“Drivers have been focused on the powertrain development so far so they haven’t complained about the brakes yet,” Gouzin laughed. “We’ll see what they think as testing goes on.”
Brakes continue to be supplied by Alcon. “We have a great relationship with Alcon,” Gouzin said. “I’ve worked with them for a long time in other series and they’ve supported us with our Formula E development, no matter how many things we want to try!”
“We’ve upgraded the lower ball joint on the the front wishbone to cope with the tough street tracks,” Gouzin revealed. “That’s the part that failed on Vergne’s car in Punta del Este. There’s a bigger ball bearing now. These parts look more like they’ve come from WRC than from F1!”
Spark has not made any changes to the rear suspension parts following upgrades brought mid-season. Formula E constructors have been able to get their hands on the rear suspension as part of their new powertrain packages and Gouzin says there are some markedly different approaches, though he can’t go into details.
The driver’s seat is the part that is lifted out wholesale in the event of an extrication. While the part functioned perfectly well, Spark felt there were improvements to be made.
“We’ve reinforced the seat and made it stiffer,” said Gouzin. “It wasn’t a request from the FIA but it was a change we wanted to make.”