Improving brake feel - track use NB8C

[Magpie]

Whilst not in the direction you want to go, that is different size masters and bias bar, I have finally managed to get the brake bias to the point that I'm happy with it. Happy with it based on the tyres and setup that is.

This is the change in braking into T3 on the National at QR. Can now brake later and at a high G force, however now have to adjust brake points and a few other things to take advantage of the brake balance.


The biggest change is in the improvement in braking. The G Plot shows that now up to 1.2g of braking, now to get it to the same as cornering...

[hks_kansei]

. Lastly, does a fluid flush help in this space?.

Possibly.

If there's a blockage or just sh*t in the lines somewhere it can make the pedal feel a lot harder than it needs to be, but normally it will also feel like the car doesnt stop super well at the same time.

In saying that, do the flush anyway, since if it's a track car the fluid has likely seen a fair bit of heat and will need to be replaced more often than on a road car.

Plus, it's a cheap and easy job to take off the list.

[The Green Goblin]

. Lastly, does a fluid flush help in this space?.

Possibly.

If there's a blockage or just sh*t in the lines somewhere it can make the pedal feel a lot harder than it needs to be, but normally it will also feel like the car doesnt stop super well at the same time.

In saying that, do the flush anyway, since if it's a track car the fluid has likely seen a fair bit of heat and will need to be replaced more often than on a road car.

Plus, it's a cheap and easy job to take off the list.

thanks mate.

[The American]

Lastly, does a fluid flush help in this space?

cheers,
Jas.

No, and for similar reasons to those mentioned above. A fluid flush helps restore the intended incompressibility of brake fluid. (Nothing wrong with fresh fluid, and a good idea to do regularly if you track, but probably not a cause of your difficulty).

Bigger master cylinder pushes more fluid, requiring less pedal travel and a more on/off operation if nothing else is changed. Braided brake lines remove the natural ‘give’ found in rubber lines (more direct again). Master cylinder stopper removes another place where the system has give. More aggressive pads, same again. If you also have track oriented front springs, which require more effort to create weight transfer when braking, that also removes some ‘give’ in the braking system. The only things left are your leg, the tyres and the road surface.

Probably not much you can do about the road surface other than look for the groove and the stickier places to do your braking. Your leg can practice modulating the brakes as they are - to essentially be more delicate. Adding sticky tyres is probably easiest - and will give your other hardware a chance to work, and will widen the range of pedal effort that you can work with before locking tyres.

The only other thing I can think of, is down grade your pads to something less agressive.

[The Green Goblin]

Lastly, does a fluid flush help in this space?

cheers,
Jas.

No, and for similar reasons to those mentioned above. A fluid flush helps restore the intended incompressibility of brake fluid. (Nothing wrong with fresh fluid, and a good idea to do regularly if you track, but probably not a cause of your difficulty).

Bigger master cylinder pushes more fluid, requiring less pedal travel and a more on/off operation if nothing else is changed. Braided brake lines remove the natural ‘give’ found in rubber lines (more direct again). Master cylinder stopper removes another place where the system has give. More aggressive pads, same again. If you also have track oriented front springs, which require more effort to create weight transfer when braking, that also removes some ‘give’ in the braking system. The only things left are your leg, the tyres and the road surface.

Probably not much you can do about the road surface other than look for the groove and the stickier places to do your braking. Your leg can practice modulating the brakes as they are - to essentially be more delicate. Adding sticky tyres is probably easiest - and will give your other hardware a chance to work, and will widen the range of pedal effort that you can work with before locking tyres.

The only other thing I can think of, is down grade your pads to something less agressive.

such wisdom.. thanks man.

[Custardtart]

Lastly, does a fluid flush help in this space?

cheers,
Jas.

No, and for similar reasons to those mentioned above. A fluid flush helps restore the intended incompressibility of brake fluid. (Nothing wrong with fresh fluid, and a good idea to do regularly if you track, but probably not a cause of your difficulty).

Bigger master cylinder pushes more fluid, requiring less pedal travel and a more on/off operation if nothing else is changed. Braided brake lines remove the natural ‘give’ found in rubber lines (more direct again). Master cylinder stopper removes another place where the system has give. More aggressive pads, same again. If you also have track oriented front springs, which require more effort to create weight transfer when braking, that also removes some ‘give’ in the braking system. The only things left are your leg, the tyres and the road surface.

Probably not much you can do about the road surface other than look for the groove and the stickier places to do your braking. Your leg can practice modulating the brakes as they are - to essentially be more delicate. Adding sticky tyres is probably easiest - and will give your other hardware a chance to work, and will widen the range of pedal effort that you can work with before locking tyres.

The only other thing I can think of, is down grade your pads to something less agressive.

All of this. The point of lock up is like the point tyres loose their grip. The more progressive the more feel andthe easier to control - BUT not necessarily the fastest. If you don’t have huge amounts of track experience it’s best to keep these two points as progressive as possible.
My order of approach would be:
Left leg training (especially mudulation over bumps)
Tyres (something with a progressive breakawa)
Less aggressive pads

[madjak]

before doing any major upgrades make sure you are doing the simple things first:

1. warm your tyres and brakes before a run.
2. drive with racing shoes. You need the thinner sole to help feel the peddle.
3. SS braided lines with a complete fluid flush. SS lines help transfer some of the feedback, pressure transfer etc from the calipers
4. Don't use high "bite race" pads. You want the pads to grip in a linear fashion. I run endurance pads (Ferodo DS1.11) which are expensive and hard to get to fit but they last 3x longer than anything else and reduce the rotor wear. It's a big cost upfront but long term they are cheaper... plus they give way better modulation and work from cold.
5. Tyres that will grip from cold (Yokohama A050s help but cost lots)

If that doesn't help you then you need to start looking at the mechanical balance.

5. larger rotor size - helps increase the area of modulation (I run 11.75" rotors, replacements are the cheapest at only $90 each rotor)
6. More rigid calipers - allows the input to match the output without delay or distortion (I run Wilwood Dynapro front and Dynalite rear)
7. Remove the booster - this might not be possible if the car is a street car. The booster acts like a pressure remapper taking your foot pressure and applying a curve to it then multiplying it. The problem is the multiplication factor can vary with revs, especially with big overlap cams.
8. Dual master setup with balance bar.