Planet 9

I must be in the minority here.
I use the brakes to slow the car then slip it into the gear I need to accelerate.

Do most people here downshift while braking so the engine compression helps in braking?

Brakes are easier and cheaper to replace than a clutch.
And it's easier to be smooth and concentrate on braking and setting up for the upcoming turn.

I voted for compression but that's because (although I haven't been to the track yet) according to the advice I read in the DE instructions that you lift, then brake, then I blip& shift with heel-to before the corner, then accelerate out of the corner. Perhaps then that should have been a vote for #1?

The only time I compression brake for a stop is if I am just practicing the heel-toe to blip through gears so really my answer is 'it depends'.
Chris

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550 Taillights, Boxster Chrome Badge, 18" Sport Wheels (17" T-Twists in winter), EVO Intake, LN Engineering IMS Bearing

Nothing slows the car better than the middle pedal! You're wasting the clutch and adding an unnecessary step by compression braking in coming to a stop. If slowing for a turn, then braking with a single heel/toe downshift to the appropriate gear should be your goal. Generally, you should be in the lower gear just before turn in, although your braking may not be complete, as you will often want to trail brake a bit after turn in to help with rotation.

Then you're not doing it right. There is no compression braking with heel-toeing.
As a matter of fact, one of the reasons for heel-toeing is not to have compression braking for instance in slippery / wet conditions when compression braking might cause the rear (in case of rwd) wheel to lock up. brakes give you much more control than compression braking for treshhold braking. Just my 2 cents.

I really meant to practice rev-matching. Otherwise the clutch is in and on with the brake.

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550 Taillights, Boxster Chrome Badge, 18" Sport Wheels (17" T-Twists in winter), EVO Intake, LN Engineering IMS Bearing

Right you are.

On the street, which is 99.9% of my driving, I never use compression braking.

At the track it is a different story. Road Atlanta has a huge braking zone after the long back straight into turn 10A. I threshold brake, and use the engine while downshifting from 5th to 4th to 3rd. Brakes + engine compression is definitely better than brakes only.

I really don't compression brake for any other corners, maybe slightly at 6. I'm not saying there aren't any other places on the track where it would be efficient to compression brake, I'm just not fast enough, or good enough to need to.

Cheers,
Chuck

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I use the brakes. 30 years ago a driving instructor told me brakes are cheap. Clutches and engines are not.

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2007 Cayman S
2008 Corvette ZO6

I learned that the engine is for accelerating, the brakes decelerating; likewise brakes are cheaper to replace than transmissions, clutches, engines. So... that said there may be times when it is appropriate while racing to add engine braking, keeping in mind people race to go as fast as possible, not necessarily to prolong the life of their cars

I think either in racing or in street driving it's the brakes that should, err, brake the car! In racing, given the car is usually on the limit you also use techniques like heel'ntoe to keep it smooth and not unbalance the car. The engine is of course also helping but you're not using it to start braking. In street driving heel'n'toe is not essential of course but will result in smoother and more satisfying experience. Why would you use your engine to brake the car? Besides straining clutch/drivetrain it makes the most unglorious, granny driving noise!

I don't know how this phenomenon on boards escalates every time, somebody says something, somebody else picks it up and it becomes LAW.

The line that breaks are cheap is so dumb ***. Compared to what? It is a wear and tear item. So what? So is a clutch. Engine? Is anybody here trying to say that if you use the engine to slow down will prematurely wear the engine or tranny???? Prematurely is what - under 100K miles? Which is what - about 5 complete sets of rotors and pads??

The problem I have with these questions is that every turn is different, is it a chicane with a 3-4 turn combo? You better have the right gear, ie engine breaking and are NOT on the breaks or is it a hard corner where you need to brake hard and downshift 3 gears? Two totally different things but if you really tell me that you go into a turn with your foot on the clutch and breaking hard then please just don't post that. Of course is it harder to brake and downshift at the same time, but what really is compression breaking? When you heel toe aren't you letting the clutch out between shifts and the engine brake, isn't that also compression braking? Honestly this line that brakes are cheaper has one single result, BAD DRIVERS. People break for everything instead of using the right gear. You go through a S combo and see 3-4 times the break lights in front of you, result car has wrong (high) gearing, cannot hold the line and drifts to the outside. I just came back from a ride out with a bunch of Boxster, flat out horrendous driving, break lights everywhere. There is a time for flat out breaking and heel toeing and there is a time for selecting the right gear and let the engine settle the car, compress the suspension and keep everything tight and allow you to power through S combos without breaking. The only reason for heel toe is to allow you to use the clutch and continue to downshift while breaking.

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VIDS
Cayman Turbo 520HP

WOW Schwabe, Tell us how you really feel

Who you calling a dumbass, dumbass?
You so upset you're having trouble typing?

5 to 2 downshift? I threshold brake and transition to trail braking and as
I'm approaching the apex I depress the clutch and slip it into 2nd, rev matching if required.

I'm having a hell of time figuring out wtf you just posted. Yes, I heel and toe and put the car in the proper gear. Through tight turns I will hold a gear and modulate the throttle which is using engine compression, but I don't down shift the car several gears to reduce the speed without braking.

Almost daily I will see/hear someone coming to halt at a light or slowing to take a turn, down shifting 3 gears slowing the car with compression before apply the brakes. It sounds cool, but is not a very efficient way to stop the car.Which is exactly what I was doing when I was told by the DI that it was not right.
Maybe I misinterpreted the original post, thinking the OP was referring to making large adjustments in speed just using the engine. Please forgive me Mr. Schumacher

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2007 Cayman S
2008 Corvette ZO6

Alright, guys - Let's please calm down - maybe this is an issue that's been discussed many time already on this forum, but it's not something to this nuts about. I'd like to remind everyone here, that calling people names is a violation of the posting rules of this site... is this really an issue to be calling people names over? I think not

I'm with green-CS here - the original poster's question is vague, because it doesn't specify the circumstances of slowing the car down. If it's when coming to a common stop at a light, as green_CS describes, I also see this all the time, and it's not the way to stop your car, imo. Will it hurt your car? Will it be a huge factor if you only keep the car for only 50k miles? No, but it will still put more stress on the drive train then just using the brakes. (BTW, Schwabe, it's brakes, not breaks... a break is something you take for coffee, or it's something that happens when you drop something breakable).

And, unless there's been a huge shift in car repair prices that I don't know about, regardless of how it comes about, replacing brakes costs less than pulling a motor to R&R a clutch or transmission, that's a fact, and it's not "dumbass" to say so.

If you're coasting to a stop from say, 50 mph with the clutch in, I would advise against it - you should keep your drive train hooked up, even when the brakes are being applied. When you get almost to a stop, put in the clutch.

Now, if this ends up becoming more of a kerfuffle over a topic this mundane, this thread will be closed, and that would be dumbass.

brad

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22-year PCA Member
PCA DE Instructor

I agree- also, if you are braking hard in AX but know you won't be changing gears, definitely use the engine to help. Since the clutch is not disengaged/re-engaged at any time I don't see how it gets ANY extra wear. Since the engine would provide the same response either way, I don't see how it gets ANY extra wear. You are using existing engine compression to help you rather than wasting it, and the braking is much better that way.

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996 GT3 lower control arms at all corners
997 GT3 front sway bar
Quaife TBD
DMC harness bar/G-force harness
Hawk HP Plus pads

This is true - in situations where a new, lower gear does not need to be selected, either on the street, AX course, or track - I've done all three when it calls for it - using the compression of the motor to help decelerate the car is appropriate.

brad

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22-year PCA Member
PCA DE Instructor

True, but I think the disagreement among some of the posters is in regard to a scenario in which a lower gear is required to achieve the desired acceleration through and out of a turn. Obviously (I thought), the purpose of heel/toe shifting is to smoothly engage the appropriate gear to facilitate speed, not deceleration. Of course, driving a sports car is all about fun. If you enjoy downshifting to slow the car, by all means do it. If you are learning the quickest way through turns, with rare exception, anything more than one downshift, even if each is perfect, is wasted effort that simply creates opportunities for error.

buying a new set of pads and rotors - $XX.XX. reading this thread - priceless

That's not how I meant this,
Any circumstances. But mainly I guess I meant while driving quickly.

When people talk about over-revs they say it's usually while downshifting.
There's a thread about sucking tire smoke into the intake while downshifting.
Unnecessary wear and tear on the equipment if you ask me.

But then maybe I'm just a dumbass.

I'm not nearly good enough a driver to convince anyone of anything but...

I'm 95% on the brakes to slow down
BUT 5% of the time I use the engine because...

1. I'm in the gear I need to get me out of a turn
2. just love the sound of it!!!!!!!