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But, i do understand what you are saYING. bUT YOU ALSO HAVE TO UNDERSTAND WHAT I AM SAYING( sorry about the caps).
If you use your engine to brake your going to save wear on your brake pads. and i dunno, what if your brakes suck and they start to fade. and at the time you don't have porterfields sitting in the garage, well that's when engine braking is gonna help.
Originally posted by BlkB14 But, i do understand what you are saYING. bUT YOU ALSO HAVE TO UNDERSTAND WHAT I AM SAYING( sorry about the caps).
If you use your engine to brake your going to save wear on your brake pads.
Brake pads are cheap and easy to install. Engines aren't.
Quote:
Originally posted by BlkB14 and i dunno, what if your brakes suck and they start to fade. and at the time you don't have porterfields sitting in the garage, well that's when engine braking is gonna help.
If you're getting brake fade in an autocross, it's not because your brakes suck -- it's because you haven't maintained them.
There is a book everyone here needs to read. It's called "Going Faster! Mastering the Art of Race Driving. The Skip Barber Racing School". Skip Barber is resposible for turning out some of the greatest racers of our generation such as Robbie Buhl, Bryan Herta, Dorsey Schroeder, and Danny Sullivan. In short, Skip Barber knows what the f#$k he's talking about.
Chapter 6: Shifting, page 94
Allow me to quote verbatim:
"What Downshifting is Really For
We ask this basic question of every racing school class. The most frequent (and incorrect) answer is, "to help slow the car down." In a racecar with good, durable brakes (the majority of modern race cars), downshifting to help the car slow is unnecessary. The BRAKES slow the car down. You downshift to get the car in proper gear to exit the corner.
There are cars with marginal braking systems, most notably showroom stock racers which have brakes designed for the demands of the street environment. Their brakes, especially in an endurance event, may fade away to nothing, at which time you use whatever you can to slow the car for the corners. In this case you certainly do use the downshifting to slow the car down - but it's a last resort."
That's "Going Faster! Mastering the Art of Race Driving" availible at a Barnes&Noble near you.
well i know why i down shift. its not neccesarly to slow the car, but i do that. I was taught to be very defensive and drive smooth. So having the car out of gear is a bad idea on the street IMHO. Cause say your are slowing down to a stop sign, you look up and notice the guy behind you barreling for you not stopping...what do you do if you arent in gear? You probaly are fu*ked, you gota put it in gear quick which probaly wont be fast enough. Then on the smoothness using the engine to slow you down like to a redlight that is empty...ok yea may wear a bit on the engine but every car we(the family) have owned get this done to them and all last over 150K miles or more. Maybe 200K might be bad for it but I would rather be safe and in gear than totaly useing the brakes alone to slow/stop the car.
Again this is on the street and only on the street. On the track all is different, your brakes do a better job at it so use them. Then again you dont have to worry about getting out of someones way while you are stoping....usualy
On the street I think a combination of both is fine. That's how I was tought. Very similar to Bowlcut. However, the track is an entirely different situation. On there you definitely want to utilize your brakes as much as possible. Two very different situations.....
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I never said it wasn't effective in slowing a car or suggest it never be used. I just dispute the claim that the combination of engine braking and standard braking will stop a car quicker than brakes alone. It will not.
And since this thread is about double clutching...
Chapter 6, page 95 in "Going Faster!"
"Double clutch downshifting
In shifting gearboxes with syncronizers, the function of the blip (Matt's note: the "blip" is for heel-toe downshifting discussed earlier in the chapter) is to smooth out the clutch engagement after moving to the next lower gear. Since most racing transmissions do not have syncos, the blip not only cushions the clutch engagement, it also allows you to syncronize the speeds of the input and output shafts. Here's how it's done.
With your foot on the brake you puch in the clutch and shift to neutral from a higher gear. You let the clutch out, and then, still in neutral, you blip the throttle.
Since, with the clutch engaged, the motor is directly connected to the input chaft, your blip easily spins up the shaft to the higher rpm. The instant after you blip, push in the clutch and move the gear lever into the (lower gear). Once it's there, let the clutch back out again. This last bit has to happen fast before the extra rpm created by the blip falls away.
By performing this series of maneuvers, you've syncronized the gears, going from 4th to 3rd without grinding. The secondary benefit is that since the clutch re-engaged in 3rd with the engine turning over at the right rpm for the road speed, you shifted into 3rd gear smoothly without lurching off the drive line."
Matt's notes and opinions:
Double clutching is unneccesary with syncros (all of our cars have them).
Heel-toe downshifting it absolutely necessary for rear drive cars in order to brake as hard as possible and NOT compression lock the rear wheels when engaging the next lower gear.
Heel-toe downshifting is less critical in front drive cars because you're less likely to compression lock the front wheels when engaging the next lower gear, but I personally feel it must be done to remain smooth. And smooth is fast.
last time i checked with truckers and how i drive engine braking is used to maintain a certin speed on grades not used for stoping, unless you have no brakes.
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