inboard brakes

[manchild]

Weren't these front inboard brakes on Lotus 72 sort of “adjusted leftovers” from 4WD car rather than original concept?

http://www.formula1news.it/storia/storia70803.htm

[scarbs]

its always struck me that inboard brakes would be a good idea. I think it would need to proven that the primary gain in unsprung weight would offset the added complexity (weight etc). Having a lighter front sprung wheel assembly would improve wheel control, especially over kerbs. having a front wheel that could be almost enclosed (i.e no brake duct or holes in the wheel rim) would be aerodynamically beneficial now that the front wing is raised so high. As BAR proved last year the driveshaft is a reliable and aerodynamically benign design. There's certainly space ahead of the drivers feet, although some packaging of the front suspension linkages may be required. However the issue of housing the brakes in front of the drivers feet and venting the enormous heat and not to mention dust would be an issue.

[manchild]

... not to mention dust would be an issue.

Now that you’ve mentioned it… recently I read about Mika Salo’s medical exam where it was mentioned that huge amount of CF dust was found in his lungs. I wonder if it has something to with him being a backmarker most of his career (breathing the air polluted by many cars in front of him) or is it a common risk for all drivers?

Since the quality of the air driver breaths depends also on position of air intake for cockpit cooling which one brings in less polluted air – nose intake or the one on top of the cockpit used by Ferrari and Renault?

[Steven]

I thought of that dust too...

My idea to integrate these brakes would be to have front air inlet like in the old days, not that big considering how small each air inlet for the brakes are at the moment. So a hole the side of the airbox would be almost sufficient. Not much aero problems there...

Second is the air+dust outlet. Suppose we use a single keel design, then I'd use the end of the keel as the outlet. Air passing by would also help to pull air out of the outlet. You would then get to have all dust on the splitter. This shouldn't be such a big problem either. Seeing how sculpted the sidepods are, if you could move up the lowest part of the radiator inlet a little bit there won't be any dust in the radiators.

any dust would then go aroud the sidepods and flow over the diffuser between the two rear wheels.

Feasible idea?

[riff_raff]

scarbs,

The drawback with inboard brake rotors is the torsional wind-up that occurs in the drive shafts. It makes the brakes feel mushy and unresponsive. Getting positive feedback through the braking system is very important to drivers. The fastest drivers are always the ones that brake latest and accelerate earliest thru a corner.

As you mention though, inboard brakes do eliminate a large amount of unsprung mass. But only at the end of the vehicle where there are drive shafts available to mount them. All F1 cars now use CRC rotors and pads, so the unsprung brake mass is a fraction (25%) of what it was with ferrous rotors and asbestos pads. The CRC brakes are also capable of absorbing/dissapating significantly more energy, without failing, than the old ferrous rotors. Unfortunately, the CRC brakes are also several orders of magnitude more expensive!

[manchild]

[Scuderia_Russ]

Some great shots there. Are they from the Historic Lotus team that maintain the old cars with some of the original mechanics?

[manchild]

No idea

[Scuderia_Russ]

Unless they are private photo's they might be taken by these guys. Sorry it's Classic Team Lotus, not Historic. It's run by Chapmans son Clive.

http://www.classicteamlotus.co.uk/Default.asp

[RH1300S]

... not to mention dust would be an issue.

Now that you’ve mentioned it… recently I read about Mika Salo’s medical exam where it was mentioned that huge amount of CF dust was found in his lungs. I wonder if it has something to with him being a backmarker most of his career (breathing the air polluted by many cars in front of him) or is it a common risk for all drivers?

Since the quality of the air driver breaths depends also on position of air intake for cockpit cooling which one brings in less polluted air – nose intake or the one on top of the cockpit used by Ferrari and Renault?

They would probably only find pollen & gold dust in MS's lungs

[Tom]

Looking at the 2CV made me consider inboard brakes, They do not even need to be connected to the chassis, just a short stub axel will do,
the only broble is that this would interfere with the hub alot, and the hot air from the brakes would be sent straight into the air intake.

[DaveKillens]

scarbs,

The drawback with inboard brake rotors is the torsional wind-up that occurs in the drive shafts. It makes the brakes feel mushy and unresponsive. Getting positive feedback through the braking system is very important to drivers. The fastest drivers are always the ones that brake latest and accelerate earliest thru a corner.

I'd like to add to this relevant post. Back in the 60's when Ford spent a lot of money chasing LeMans, they did a lot of pioneering groundwork in analysis and information gathering. They discovered that when under full load, the driveshafts of the GT-40 flexed up to 270 degrees. Remember, a driveshaft can be treated as a torsion bar.
So if you have an inboard front brake system, it has to be remembered that when the brakes are applied, that front driveshaft can flex a lot, leading to this massive sponginess the driver would feel. So although the theoretical advantages of locating the brakes on the sprung part of the car are there, the driver would be outbraked in almost every scenario.

[joseff]

Yes and no... modern carbon/carbon brakes also have this lag between the time you stand on them until they're actually hot enough to grip like mad.