No Brakes!!

[mikeonthebike]

I sound a lot to me like this was a situation in which the stock brakes were not up to the job, particularly the rear drums. If the rears were not doing a balanced share of the job (not uncommon with rear drums) then not all the grip available across all four tyres was being used.

In which case, yes a brake upgrade would make a difference as would the correct adjustment of the brake bias (so often overlooked). The next question would be, do you think fitting even bigger brakes would have continued to make a difference? I strongly suspect not.


Scaff

I agree with you on that. After the brake upgrade which stuffed as big of brakes that we could fit in 17" wheels I don't think any bigger brakes would have helped any better at that point. One big reason would be that bigger brakes would have needed bigger wheels, lower profile tires to fit in the car and I think we would have been counterproductive at that point

 

[Scaff]

I agree with you on that. After the brake upgrade which stuffed as big of brakes that we could fit in 17" wheels I don't think any bigger brakes would have helped any better at that point. One big reason would be that bigger brakes would have needed bigger wheels, lower profile tires to fit in the car and I think we would have been counterproductive at that point

Indeed. Not to mention the issues you may have encountered with cooling, the increase in un-sprung mass, etc, etc.


Scaff

 

[mikeonthebike]

Indeed. Not to mention the issues you may have encountered with cooling, the increase in un-sprung mass, etc, etc.


Scaff

totally

 

[Tower Turn 13]

I think your arguing semantics because at no point have I said that you don't need brakes.

Brakes slow the rotation of the wheel and tyre assembly, however its the tyre/road interface that determines how quickly you slow and stop your car.


Scaff

Why don't you people learn something instead of being so stubborn and self-important to feel you gotta chime in even if you don't have the knowledge-base to do so? I've enjoyed each of Scaff's (and his sources) posts/articles. Sometimes it's good to debate, and I thank those who do because it forces Scaff to be very specific and address various points. But then sometimes it's also good to shutup and learn something. I know I have. 👍

EDIT: not everyone is knowledgeless in this thread, quite a few people are having good debate. Just saying in general a few seem to be just kind of arguing for the sake of arguing.

 

[calico]

An interesting read.
http://www.wcengineering.com/articles/brakes.html

 

[Scaff]

An interesting read.
http://www.wcengineering.com/articles/brakes.html

It is an interesting read, covering the basics well in layman's term.

It's nice to see the importance of tyres noted "For me, I don't believe that it is possible to have too much traction" and a correct brake-down (pardon the bad pun) of rotors.

"This power can be referenced in Newton-meters of torque." and "Even, a reasonably larger diameter rotor will provide increased stopping power."

Torque (stopping power) at the rotor is directly proportional to torque at the wheel and the tyre (its a 1:1:1 relationship as all three are connected), which allows the traction available at the tyre to be used to its fullest. Which brings things full circle.

You can't increase traction available at the tyre, but this does ensure you are able to utilise it fully.

This ties in well with the following (which does move away from the layman side of things)...

http://www.stoptech.com/docs/media-center-documents/the-physics-of-braking-systems.pdf

...specifically the sections on the Rotor, which covers the calculation used to figure the torque (or stopping power) and how it is directly proportional to the torque at the tyre (that 1:1:1 relationship again).

Also the section on the Tyre which then takes that torque (from the Rotor to the Wheel to the Tyre) and discusses the calculation used to relate the toque and tyres rolling radius to the force reacted between the tyre and the ground. Its important to note however that the actual amount of slip generated (i.e. the limit of traction available) is clearly defined as a function of the tyre's.

"The amount of slip generated will be a function of the tire's output characteristics (the mu-slip relationship)"


The sections on the importance of selecting the right rotor/pad combo, size/thickness of rotor and pad size/material is also well coved, detailing why the biggest/thickest, ect. is not always best.


Nice link many thanks


Scaff

 

[PredatorPie]

Scaff thanks for your excellent points and respect for your patience. 👍 This is a great thread, hilarious thanks to some ignorants and educational thanks to you and a few others.

 

[Ecchi-BANZAII!!]

This might bring calico to his senses.
There are ten upgrades for brakes in GT5.

Braking Bias level 0 (0/0) (Fake stock)
Braking Bias level 1 (1/1)
Braking Bias level 2 (2/2)
Braking Bias level 3 (3/3)
Braking Bias level 4 (4/4)
Braking Bias level 5 (5/5)
Braking Bias level 6 (6/6)
Braking Bias level 7 (7/7)
Braking Bias level 8 (8/8)
Braking Bias level 9 (9/9)
Braking Bias level 10 (10/10)

The better the brakes are, the easier the brakes lock the wheels.

To us that doesn't use his logic well, we already know why the game doesn't need braking upgrades since GT5 don't simulate brake wear.

 

[Schwartz]

Woah, hold on. The brake numbers are brake balance between the front and back wheels, not strength. While setting balance more towards the front may give you a better stopping time, it doesn't make the brakes any stronger per se. So 2/2 means the same as 8/8 and 10/4 is the same as 5/2.

 

[dr_slump]

Woah, hold on. The brake numbers are brake balance between the front and back wheels, not strength. While setting balance more towards the front may give you a better stopping time, it doesn't make the brakes any stronger per se. So 2/2 means the same as 8/8 and 10/4 is the same as 5/2.

Did you test it?

Turn ABS off and compare 0/0 with 10/10.

 

[nomis3613]

I sound a lot to me like this was a situation in which the stock brakes were not up to the job

Which is how many of the cars would be in GT5.

Not to mention when we ditch the comfort hards for a set of racing softs, there is no way that the stock brake system be able to hold the tyres at peak braking force, even for a single stop. Therefore brake upgrades would reduce stopping distance.

 

[M_thoroughbred]

The laws of physics, along with brake and tyre manufactures and race engineers and designers the world over disagree with you. So personally I like the company I am in.

As long as your current braking system is capable of locking up your tyres then increasing rotor size and/or fitting more powerful calipers will not stop you quicker. As long as your tyres are locking then they are your limiting factor not your tyres...



Source - http://www.stoptech.com/tech_info/wp_brakebiasandperformance.shtml

and

http://www.stoptech.com/tech_info/The Physics of Braking Systems.pdf

...read the above two and then come back.

BTW - You may also want to know that I have taught the fundamentals of vehicle dynamics within the motor industry for over a decade. This a subject I know a bit about.

Scaff

agreed

 

[ITCC_Andrew]

The laws of physics, along with brake and tyre manufactures and race engineers and designers the world over disagree with you. So personally I like the company I am in.

As long as your current braking system is capable of locking up your tyres then increasing rotor size and/or fitting more powerful calipers will not stop you quicker. As long as your tyres are locking then they are your limiting factor not your tyres...



Source - http://www.stoptech.com/tech_info/wp_brakebiasandperformance.shtml

and

http://www.stoptech.com/tech_info/The Physics of Braking Systems.pdf

...read the above two and then come back.

BTW - You may also want to know that I have taught the fundamentals of vehicle dynamics within the motor industry for over a decade. This a subject I know a bit about.

Scaff

There are about 6 direct factors to stoppong distances. I won't re-mention tires. They are: Surface conditions (snow, rain, dirt etc.,) vehicle mass (weight transfer, distribution and cornering load,) tire grip (size, profile, compound,) braking efficiency (are you braking too late? Are you braking, but your brake pads and rotors are worn and no longer create friction? Are your brakes overheating?) and corner entry speed. A Formula 1 car stops well, because of downforce creating lots of grip. Think back to Spa 2010, when it started to rain, while the cars were on dry tires-they didn't stop in time. It all comes down to available grip. Even in heavy cars, the load affects grip. A Land Rover takes longer to stop because the tires have SO MUCH to stop. Your Buick might be the same, thread poster. It may not have sufficient grip to compare to the other cars, which are lighter and have downforce. DON'T QUESTION SCAFF. The man is smart. Formula 1 cars run their carbon ceramic brakes to reduce brake fade and unsprung weight. Consider the weight of street brakes against carbon ceramic.


EDIT* To further clarify my reasoning, I'll include some simple steps to explain an integral idea:

1.Buy a bicycle with V-brakes. These clamp directly onto the sides of the rims.
2. Hold bike off the ground.
3. Spin front tire.
4. Apply front brake.
5. Notice that tire stopped turning immediately.
6. Ride bicycle.
7. Fully engage rear brake, to avoid going over the handlebars.
8. With rider on bicycle, there is greater forward inertia. This means the force acting against the brakes is greater.
9. If rear tire does not lock, get better brakes.
9.5. Re-run step 7 with better brakes, strong enough to lock the tire.


Observations: Inertia will increase braking distances: Newtonic physics "An object in motion..."

Grip is the deciding factor, given that the brakes are powerful enough to come JUST short of locking up. The best braking distances on dry pavement use ABS to modulate the brakes UNTIL THE THRESHOLD just before loss of grip.

 

[zampination]

I agree with Scaf at all times except in one thing. i don't believe that all cars in GT5 have brakes capable off locking the tyres so that GT5 don't need brake upgrades.

And as scaf stated in the early pages of this thread saying that nowadays all cars have their braking system capable off locking the tyres, Then what about old cars before 70's for example???
Why can't i upgrade the braking system of an old car to fit a modern's car efficiency in braking??
So, even so that GT5 does not model brake-fade physics, i still need brake upgrades to equip older cars with better braking system in order to go faster in a track and decrease stopping distances.

At this point i dont have my ps3 nearby to test it out, but if my memory is right i remember that the buick special and an old dodge charger srt lacks of braking power in compare to modern cars in the same weight ratios.
If someone could test it right now, many others would be grateful.

After a test like this (if it is proven so), then we have proof that a brake upgrade is really needed in GT5 even without modelling brake-fade.

And since someone is willing to upgrade his old muscle car and spent money on it, it is not fair that he can't have the option to put the same brakes that an F1 car has or a modern GT-R has and so on.