Would it be possible...

"Full of the sound of the Gran Fury, signifying nothing." (granfury) 05/08/2018 at 23:57 • Filed to: None

0

12

...to have both inboard and outboard brakes on a front axle? How about dual calipers on a rotor? Would either of these lead to better braking performance, or would it just be lots of weight for minimal gain?

Montalvo > Full of the sound of the Gran Fury, signifying nothing. 05/09/2018 at 00:11

2

Yes you can. Typically inboard brakes aren’t worth the hassle it’s why you rarely even see them in Motorsport. Recently Hot Rod Garage had a setup with the handbrake that went to additional calipers on the front discs since their Malibu had drums in the rear. So possible? Yes. Practical/efficient? Nope. You are better off having one well designed and sized caliper.

Nick Has an Exocet > Full of the sound of the Gran Fury, signifying nothing. 05/09/2018 at 00:27

1

No reason you couldn’t do it.

Cons: Not efficient, extra maintenance, cost.

Pros: In theory, you would decrease heat caused by braking and therefore eliminate some brake fade

facw > Full of the sound of the Gran Fury, signifying nothing. 05/09/2018 at 00:43

1

Having more pistons and a larger brake pad is basically the same as having multiple calipers on a single rotor, so that is more or less done. I don’t see any reason you couldn’t have both inboard and outboard either for that matter, though that’s obviously a lot more weight and complexity.

As a practical matter though, it seems like in most applications you are limited by the tire anyway. There’s no point in exerting braking force beyond what is needed lock the wheel. If the car is sliding rather than rolling, braking more isn’t going to help it stop faster.

sony1492 > Full of the sound of the Gran Fury, signifying nothing. 05/09/2018 at 01:04

1

Dual calipers are used on drift cars connected to a hydraulic hand brake. But that is not about increasing brake force, just to lock 1/2 of the braking system remotely(with brake handle).

If your buying an adapter to fit a second set of calipers than chances are you can afford an adapter to upgrade to larger calipers that will include a larger rotor (which will hold more heat and take longer to get to max operating temp)

I’m guessing but two sets of calipers and rotors per wheel may not be done because the gains don’t outweigh the additional rotating mass and because, are current brakes really needing that? I mean one can just slap a huge rotor on there and route ducting to it.

AuthiCooper1300 > Full of the sound of the Gran Fury, signifying nothing. 05/09/2018 at 02:42

2

Years ago, when wheel sizes basically stopped at 15", it was not uncommon for high-performance cars to have dual calipers, at least on the front axle. Case in point, the (old) Maserati Ghibli.

For the same reason some cars were homologated in Group 2 (maybe also in Group A, a little later, although technology had moved on quite a bit by then) with dual front calipers (which of course usually meant a different kind of hub carrier). Racing/rallying versions of the GTV6 (and probably the 75) used that setup. Better designed calipers made that kind of arrangement redundant.

Alfasuds and Alfasud Sprints had in-board front disc brakes. Alfa 33s and Sprints, both derived from the Alfasud, had outboard ones. I’ve heard of some people fitting both systems. It works but I doubt there is a serious improvement in a car of such (relatively) little performance.

The whole point of having inboard brakes was to reduce unsprung weight (letting the dampers work better, for example). 60s-70s F1 cars used to be like that. Towards the end of the 70s having cleaner “wing car” aerodynamics and ground effect was finally considered a better compromise, so they were abandoned.

Of course on a very flat racetrack there is not so much need to control sudden up and down movements of the wheel so racing teams running Alfa 75s, for example, started moving their rear brakes outboard (which also had the important side benefit of stopping heat transfer to the gearbox). Besides, damper technology has advanced enormously since the 60s-70s, and emergency repairs on outboard brakes are obviously much easier

Early versions of the Silver Arrows had inboard brakes both front and rear, with front “brakeshafts” added specifically for that purpose. It seems the root cause of the accident that killed Rindt in a Lotus 72 (as in the picture) was failure of one brakeshaft, the two-wheel drive Lotus 72 having inherited its front inboard brakes layout from the four-wheel drive Lotus 63.

AMGtech - now with more recalls! > Full of the sound of the Gran Fury, signifying nothing. 05/09/2018 at 03:23

1

Maybach 57/62 use dual front calipers, as do some older AMG’s (some 221 and 216 for example).

McMike > Montalvo 05/09/2018 at 05:27

0

^ What he said.

Your time is best spent putting in the effort for a single disk setup.

And inboard brakes, while an interesting quirk, are a pain in the ass.

BigBlock440 > Full of the sound of the Gran Fury, signifying nothing. 05/09/2018 at 07:50

0

If you can break the tires loose with one, you wouldn’t gain anything by adding more clamping force to an already skidding tire.

MiniGTI - now with XJ6 > Full of the sound of the Gran Fury, signifying nothing. 05/09/2018 at 08:32

0

My Jaguar has inboard rear brakes and dual piston front brakes.

e36Jeff now drives a ZHP > Full of the sound of the Gran Fury, signifying nothing. 05/09/2018 at 08:38

0

The Maybach 62 had dual calipers on the front rotors.

RamblinRover Luxury-Yacht > Montalvo 05/09/2018 at 09:44

0

Secondary calipers for e-brake was a thing on Jags for ages and also crops up on Aston Martins. On the rear wheels, of course.

Mustafaluigi > Full of the sound of the Gran Fury, signifying nothing. 05/09/2018 at 15:20

0

How often is braking limited by the calipers? It’s more the limit of the tire. At most you would have some heat savings but your better off designing better cooling or a larger rotor/larger caliper.