Gernby

The reason is that you should accelerate out of a turn, and your gear selection and clutch engagement should occur before entering the turn. If you engage the clutch in the middle of a turn, you can disturb the balance of the car.

spapdx

xviper

I've answered this question a few times in the past and I was hoping someone else would step up and give their take on it.
Gernby is correct and his answer is particularly applicable when competing. But for daily, routine driving and driving in general, having the car either in neutral or with the clutch in (ie, disengaging the power from the drive wheels), or in other words, "freewheeling" or "coasting" (IMO) is not a sign of car control. Even if you row through the gears as you slow down, you can never be certain what your engine is doing in relation to what your drive wheels are doing. These should be in harmony ("in synch") as much as possible. It's like "being in control of your car" as opposed to "the car being in control of you".
Of course, there are always exceptions to the rule. One of these is if you are trying to slow down briskly or stop on an extremely slippery surface like ice, snow, loose sand, leaves, etc. Here, engine compression can easily "over-brake" the car and cause you grief. In these sorts of circumstances, it's better to let the ABS do what it can. AND there are exceptions to this too. But we would go on and on and on....

dwb1

This has always been a very interesting thread . As I said before and will state now ,brakes stop the car and the motor makes it go.
When people talk about a car going into a curve and braking before , during or some other method . The car transfers weight while under braking , the weight of the car moves forward over the center of gravity ( as has been stated many times ) by braking before the curve and having the transmission in the correct gear ( a RPM that puts the motor in its power range ) allows the driver to transfer the weight back for correct handling in the corner . ( many people find the S-2000 wants to push in a corner when driven hard ) this is not the case in most instances , it

Chazmo

[QUOTE]Originally posted by dwb1
[B]
1.

Tedster

Let me try: you can only stop the car as fast as the grip of the four tires will allow.

If you can lock up the tires (or cause ABS to activate) with the brakes, then you are stopping as quickly as you can. Using engine compression can't help, 'cause the tires are doing all they can.

That's the slightly slimplified version, but is the most important point.

[Less simplified details: you can think of engine compression as an alternate method of getting the (rear) tires to do some stopping work, instead of the brake pads on the discs. Barring an emergency situation, (e.g., pads worn though, rotors cracked and fallen off, fluid gone) the S2000 brakes should always have plenty of power to lock up the tires. You can achieve a 'poor man's brake bias' by using the engine or parking brake to do more braking with the rear tires, but I don't know why you would want to other than to induce a spin.]

Hope that makes some sense,

Ted

slick rick

The best way -- most efficient, which applies to agressive/race driving is to slow that car down with treshold braking while balancing downshifts with delicate heel and toe.
This way you get both: strong braking performance and the ability to use the engine torque (which we don't have a lot of) to "fine tune" or balance the car.
In skip barber (years ago) they talked about the "traction circle" which is basically an explanation about the ability of 4 contact patches to handle force. You can only max out the brakes to one point. Whether you got there by using brakes or the engine, you only have a finite amount of traction available to you. You have to be able to do both: brake and downshift.

dwb1

The friction between the track or road and the tires determines the braking ability of a car . The calipers and rotors only convert motion to heat . You can add the largest rotors and biggest pistons in a caliper and all they can do is lock up and create a slide . The ABS pulses on and off , keeping the tires just turning , giving you control and allowing the car to stop in the shortest distance . ( sliding tires get hot and don

Chazmo

Thanks, Brad. OK, I do understand what you're saying now. As Ted surmised, you can only stop as fast as the grip of the four tires will allow.

I believe the term "sticky" that you're using is actually "stiction." If I'm recalling this right from Physics, stiction is the resistance of two objects in contact from breaking contact. In the case of tire and road, it's synonymous with "grip."

Have a nice weekend!

Gernby

Don't forget that better brakes (larger, etc.) will improve the driver's ability to control lockup. If the braking force causes the tires to slide, braking ability is reduced. If the ABS engages, braking distance will increase.

Engine braking makes modulating the brakes more difficult, since the engine is going to exert a set amount of force, on the rear tires only, that changes over the RPM range. Since the brake's front / rear bias is fixed, you cannot expect throwing extra, variable, rear wheel braking into the equation, without expecting a reduction in effectiveness.