The Next Brake Upgrade!

[beetle1303]

Originally Posted by Astromic

My last question is why we all need to upgrade to a bigger system with bigger calipers and wider rotors, and why couldn't we just add a servo(vacume assist brakes), and save of the headache ...

The reason for bigger brakes arise from the increased need for braking power and not a matter of drivability. A certain brake combo (rotor and caliper) can handle up to a limit. This limit has to do with car weight, max velocity, weight distribution, aerodynamics, gearing and a few other factors that im missing now. Thus the stock beetle traveling at 100km/h with stock brakes will brake suffiently, the same beetle traveling at 200km/h will need bigger brakes due to increased velocity.
Another thing is that the more pots there are in your calipers the more linear is their performance. Think of a 4pot caliper. the first set of pots is small, because you dont need all this braking power at low speeds (less pressure on the pedal), but when you would need to make an emergency braking or serious braking (track day, spirited driving) you need all the power. What happens is that the wheels will not lock easily.
Try to descent a mountain, while braking slowly through the whole distance, and doing "spirited driving" and braking hard only when is needed while using engine brake as well. On the second test you will see that at the end you will have bit of brakes left. This means that the first way exceeds the braking capacity of your brakes, simply they are overheating, pedal travel will increase due to overheating brake fluid and before you know it you are left with no brakes.

Fitting a servo will make things worse because you would lock the brakes more easily. I would say if you want a servo, you can fit it, but use bigger brakes. There is also a matter of space in the humble beetle, but there are some ways to get past around it.
sorry for the long post. Hope its abit more clear now...

Chris