DO You Know What Brake Caliper Rigidity / Deflection Mean?

"Braking Confidence" "Braking Feel" "Spongy Brakes" 'Soft Pedal" Have you ever wondered what journalists and car reviewers mean when they say these things? Or why all the performance cars, sports cars, super cars have these huge fancy looking brake calipers?
Well let's take a look at a hypothetical situation where I simulate in FEA the deflection of three style of brake calipers at the same clamping force.
FEA Simulation Parameters:
Clamping Force was held constant at 1952 lbs between simulations, but varied line pressures.
Steel Stiffness was assumed to be 190GPa and Aluminium Stiffness was assumed to be 69 GPa.
Test Cases:
DC2R - Steel Sliding Single Piston Caliper
TL-S Brembo - Aluminium 2 Piece Bolted 4 Piston Caliper
Genesis Brembo - Aluminium Monoblock 4 Piston Caliper
And the results are in... see for yourself what the advantages are!!!

[@GibbysGarage15]

Interesting to see and explains why commonly-seen single piston calipers have such poor brake feel. Not to mention pads tend to wear unevenly due to their design when driven hard. I'm a big fan of my 6 piston wilwood kit. Braking "confidence," although it is something that's not really measurable, is something every driver that takes their car to the track is after. Nobody likes a sloppy brake pedal with lots of travel. Appreciate all the hard work put into this, fascinating to see!

[@FormulaDeltaOG]

Gibby's Garage thanks for the positive comments!!! Lots more to come 🥳

[@SebastianMocny]

Teach us about differentials! I know you worked on a Torsen LSD years past.

[@javiergenis7982]

very good video, can you make a tutorial on how to do this CAE calculation of brake calipers in fusio 360? I am very interested, thank you

[@mohamadalinagafdari7384]

Hi

[@CharlesNam]

It would be also interesting to incorporate differences in material properties in cast aluminium commonly used in low cost monoblock calipers and forged aluminium in higher cost two-piece calipers. Obviously forged material having inhomogeneous and non-isotropic properties make that difficult but approximations could be made i reckon.

[@FormulaDeltaOG]

Charles The strength difference will vary significantly with different grades of aluminium however the stiffness of the different grades of aluminium will not vary very much (69-72GPa). Since the calipers operate entirely in the elastic region the anisotropic properties will also play a very small factor in this. Inhomogeneity in the material would definitely throw things off, but hopefully the quality department of these brake manufacturers catches those defects before they make it out the door

[@CharlesNam]

@@FormulaDeltaOG good point i was thinking that after i left that comment. Its only going to be relevant in extreme heat and load situations where yield occurs (as it does sometimes in real life), not during normal use.

[@FormulaDeltaOG]

Charles Nam no worries, it’s always good to see people like you ask good questions to further people’s understanding of the material that is being presented. Would be very interesting to get an in-depth understanding of the design parameters that a company like Brembo go through to produce some of these products

[@kouki.zc6]

Makes me think of the time where I drove a friend's STi and I thought the car had stiff brakes with poor feedback. I originally attributed it to the pads but now I wonder if it was the calipers. I was coming from an RSX which uses a steel single piston sliding caliper and I thought my brakes felt easier to control. Could caliper deflection actually aid/help brake modulation or am I out to lunch?

[@GibbysGarage15]

I would THINK that you would always want to minimize caliper deflection. It just creates an inconsistent feel. If you want to fine-tune your modulation efforts, better to go with a pad that has the characteristics you're after. There's a lot of options out there!

[@wildc4t525]

Would it be possible to get a copy of the brembo track pack model? I've been working through a ton of OEM 4-piston calipers to modify my car and it's getting quite expensive to order and test fit them. I'm up to 7 different calipers now.

[@hakuna7931]

Hi there! What software did you use for analysis?

[@FormulaDeltaOG]

In this particular video the software that was used was fusion 360