| It might seem counter-intuitive but there are so | | | | In actuality, the driver gets on the brakes on |
| many details that these NASCAR teams take into | | | | speedways in the following instances: |
| account when it comes to choose the proper brake | | | | 1. Heavy, to come down pitroad for a greenflag |
| package to run at Daytona and Talladega. The brake | | | | pitstop. It's important the pedal is there. Most times |
| demand is of course less as opposed as | | | | the spotter comes on the radio to remind the driver |
| Intermediates and Short Tracks in terms of pressure | | | | to pump the brakes. |
| and temperature but there are other variables and | | | | 2. Heavy, to avoid the wrecks "the Big One". At the |
| parameters that come into play and every team | | | | time I am writing this article, todays race at Talladega |
| must be aware of. | | | | had to 2 big ones one involved R Newman, the other |
| The main target for a speedway car is the | | | | one M Martin and Talladega is statistically known to |
| aerodynamics, they even clear coat the decals, | | | | have at least one |
| every little thing counts. | | | | 3. At Daytona, the car handling comes into play. The |
| As far as the brakes are concerned, the brake | | | | tires get old or the car gets tightened up so the |
| package that includes the caliper/rotor combination | | | | driver might just tap the brakes to help the handling. |
| must be as light as possible but still strong enough to | | | | 4. The leader might tap on the brakes a little bit to |
| come down pitroad and slow those 3600lbs cars | | | | cause the chasers to step on the brakes. Absolutely |
| from 195 to speed in pit road safely and in the | | | | never lift off the throttle on speedways, not to kill |
| shortest amount of time. Over the past years the | | | | that momentum, with NASCAR mandating the |
| brake makers have made huge efforts to come up | | | | carburator restrictor plates, it takes too long to the |
| with a proper engineered brake package and the | | | | engines to gain RPMs back. |
| state-of-the-art has come a long way. As mentioned, | | | | 5. Drafting and avoing to get bumper to bumper. |
| the weight is crucial for every component that is on | | | | With the new rule NASCAR established, they want |
| a race car, especially for the COT where the teams | | | | to see day light between bumpers over the corners, |
| have been left in a little box to work within, the | | | | so again the might just get on the brakes a little bit |
| weight of the brakes and unsprung weight can give | | | | but never lift the throttle. |
| them an edge to be more competitive than the next | | | | Getting back to point #1, it takes a lot of clamping |
| car. Some pads prototypes had been developped, | | | | force to slow down these cars so the caliper piston |
| with full thickness but party made out of carbon and | | | | size is bigger than std. This is because of 3 reasons |
| few mm of real friction material to reduce the pad | | | | mainly: a. The brakes are cold so the pads are not |
| weight. | | | | within their operating temperature, as a result the |
| Second important requirement is to reduce the drag | | | | grip is mechanical only not thermo-chemical. b. The |
| of the brake pads "rubbing" on the rotor faces. Of | | | | pad materials for speedways are usually less grippy |
| course turning left only, the pads facing inward the | | | | than those ones for Short Tracks and Road Courses. |
| race track inevitably rub the inner rotor faces due to | | | | c. The rotors are usually of smaller diameter - and as |
| lateral G, we see this especially at Daytona rather | | | | a result the brake effective radius is smaller - to save |
| than Talladega that has got higher bankings. To | | | | weight and reduce the inertia due to rotating mass. |
| overcome this dragging issue the calipers and pads | | | | The Master Cylinder size is also bigger than a std size. |
| are usually equipped with a sort of pad retraction | | | | This is because of 3 reasons: a. To run with a bigger |
| device such as springs to keep the pad off the | | | | caliper but at the same time keeping same BIAS, |
| rotors. | | | | pedal ratio, etcc.. b. To compensate the volume of |
| Plus, still related to reducing the brake drag, is the | | | | fluid due to the rotor runout and vibrations pushing |
| instantenous release, that is the capability of the | | | | the pads back, this happens running at big tracks for |
| seals to pull the pistons back everytime the driver | | | | many laps without never hitting the brakes then |
| gets on the brakes and releases them. It's just a split | | | | suddently on the brakes, the pedal feels now longer. |
| second but it makes the difference between win the | | | | c. To get more modulation coming down in the pits |
| race and finish mid-pack at Talladega. The release can | | | | and reduce the possibility of locking up the front |
| be measured at the dyno or by performing speed | | | | wheels and get past the pitstall - the speedway |
| coast down test sessions at the proving grounds - it | | | | brake package is typified by a brake BIAS towards |
| is of course crucial for this type of test to quantify | | | | the fronts as opposed as Short Tracks. |
| the influence of external factor such us wind, | | | | Brakes problems can happen on speedways most |
| temperature, tires, track conditions, ecc... To improve | | | | times due to rotor thermal shock coming down |
| the release the calipers come with special seals called | | | | pitroad with cold brakes. |
| High Roll Back. The other thing they can do is to run | | | | The hardest part is to get the brake package to |
| brake pad materials which are softer than std for | | | | work in harmony with the whole car. |
| better release. | | | | |