ENZO vs PORSCHE GT

[LateNightCable]

Does anyone know what that flip-up camera looking thing is between the headrests of the Carrera GT?

Hey Izzy, I have a question for you since you're into racing. Why is it that Indy and F1 style cars seem to be the only ones with inboard mounted brakes? Since removing unsprung weight from the wheels is important, I wonder why it's not a more popular arrangement on exotics like the CGT and Enzo, where no one cares about ease of maintenance.

[rvanleersum]

Reason why you dont see the same brakes on open wheel race cars and exotics is, i think, because brake temperature issues. With open wheel cars you see air intakes which cool the brakes. An intake like that inside a wheel wheel would render it useless for anything asides taking up space. Correct me if I'm wrong.

[LateNightCable]

No, I don't think thats it. Regular performance cars have brake ducts that handle cooling alright. Brake cooling doesn't really take up space inside a wheel well. If any cars don't need inboard mounted brakes, it would be open wheel cars, because their wheels are of course out in the open air. But they seem to be the only ones that have them.
Perhaps it has something to do with the fact that the suspensions of open wheel racecars are not supported in a conventional way, but that doesn't explain why closed wheel cars don't use that brake setup. Why other cars don't use it is a mystery - it's odd.

[izzyloveslizzy]

Actually, heating IS an issue. So much so that it becomes a fire-hazard. But it's one of the smaller issues. The main thing is that in-board mounted brakes are better at stopping cars that have a lot of momentum but need to protect the braking mechanism from damage or debris. Outboard-mounted brakes are also more easily damaged. So in racing it makes sense to have in-board, eventhough they're harder to access for cleaning and maintenance. Military vehicles mostly have inboard-mounted disc-brakes. F1 and Indy cars have inboard because their wheels stick out of the car, as you already must know. Unsprung weight can also be reduced if you mount the brakes inboard instead of outboard. I hope that answers your question.

[LateNightCable]

Yeah, that helps. But so many racecars have outboard brakes, and they are just as prone to debris. The unsprung weight benefit is the reason that I wondered why it isn't a more popular arrangement.

[izzyloveslizzy]

I actually don't know of any Indy or Formula 1 style cars that use outboard-mounted brakes instead of inboard-mounted. And I'm not sure why they WOULD use outboard-mounted instead of inboard-mounted.

[LateNightCable]

I'm talking things like LeMans racers, and other closed wheel cars. It seems odd that inboard brakes would be restricted only to F1 and Indy cars.

[izzyloveslizzy]

No it doesn't seem odd at all if you take into consideration everything I said, about the disadvantages of outboard brakes when they are used in cars that don't have wheel wells for their wheels. Wheels that are out of the car are more prone to debris and easier to damage, so it makes sense to ave inboard-mounted brakes. LeMans racers have their wheels inside the wheel-well. Inboard-mounted brakes aren't needed when the car's wheels aren't out in the open.

[LateNightCable]

Thats what I think is weird, closed wheel LeMans racers don't need the inboard brakes, but I would think the builders would still want to use them to save on unsprung weight. It must have something to do with racing regulations, and it may be just too inconvenient to service on a roadcar, even for the Italians.

[electrofreak]

Enzo.