2k4_8

Is this detrimental to the clutch or anything? Now let me explain first. Most people think that when I talk about engine breaking, that I just let the clutch out entirely and let the engines natural winding down slow it down. This is not the case. I will try to explain it as best as possible. Lets say I am coming up to a corner or a hard stop at 65 mph. I will put it into 2nd and begin to let out the clutch. Just get it right to the edge of the friction point. The motor will not go up in revs hardly at all, so that I am still at about 2kish rpms. Basically, you know when you downshift, and the motor isn't rev-matched, and you let out the clutch to early and it jerks as it slows down way fast? Well what it is is actually keeping it at that point where it was trying to slow the car down, but without the revs going up. Actually using the clutch to decelerate similar to if you were to slip the clutch while you were starting....so I reiderate....is this bad? Also, if anyone could tell me what this technique is called, that would be fantastic.

Thanks

Gambit

sounds like you're burning the crap out of your clutch.

just use the brakes...break pads are a lot cheaper than a new clutch

Galen Darkmoon

As the oldtime racers said.
Brakes are for slowing. Gas is for goin.

mysql101

yeah, what you're doing is going to burn up your clutch.

what you should be doing is rev matching, blip the throttle and get the revs up to where they would be in the lower gear, then let off the clutch smoothly. If you do it right there will be no jerky motion and you will not be wearing out the clutch.

something else to consider is that when you engine brake, you'll use up less fuel than you will at idle.

DarkBrew

Heal 'n' toe to blip the throttle for a nice rev-match while braking. If you master this your driving enjoyment will improve.
You will be replacing your clutch early if you keep using it as a brake instead of the engine.

2k4_8

I guess I should have also said that this isn't something I do during daily driving. I think I picked up this from driving cars previously that didn't have the necessary stopping power. I usually used it if I needed to stop quickly if I was for example coming into a corner way to hot or needed to stop fast to avoid a crash. I will discontinue this practice from here on out.

Rev-matching is a necessity in this car when down shifting unless you have an in-law in the passenger seat and want to bounce their head off of the dash.

mcgregor129

i gotta admit, I am definately guilty. I should've realized that this wudnt be good for the clutch. O well i guess ill stop doing it. Actually, the only reason I normally did it was after I washed the car, I wud get paranoid that when I break properly, the wheels wud get dirtier faster. kinda crazy.

John V

iTrader: (1)

The cars you were driving previously had something seriously wrong with their brakes.

Good idea to never do it again.

shikataganai

clutches are a whole lot more expensive than brake pads. do the math.

2k4_8

No, nothing wrong....just not sports cars : D Of the cars involved one was a 1993 Eclipse 1.8l, 1994 Ford Ranger, and a 198x Subaru Wagon, so nothing close to 4 wheel abs and over 12.5 inch rotors up front

mwood

this thread is causing severe distress to the mechanically empathetic part of my being...

EnzymaticRacer

The irony is actually that you were lengthening the time it took for you to stop.

"engine braking" only actually has braking properties for a split instant. Once that instant is up, the engine is actually propelling you forward, counter-acting any input by the brakes. With the clutch out, the inertia of the rotors/pistons is actually still providing power to the wheels. The absolute fastest way to stop ANY car is by using ONLY the brakes...


but, as has been said earlier, brake pads are a lot cheaper than a transmission....

John V

iTrader: (1)

Ahh... no. Not true at all.

With the throttle closed, the engine is a huge drag on the vehicle because of the internal pumping losses. In a fuel injected engine, there is no fuel being shot into the engine when the throttle is closed (unless the engine is at idle).

edit: under full braking I can see what you're saying. But your first sentence still makes no sense.

mysql101

lol

Next time you're out driving, do a little test for me.

While cruising in 4th gear on a city street - drop it to 3rd and completely let off the throttle. Then do the same test from 4th but this time put it into neutral and see if you slow down any faster.

John V

iTrader: (1)

That's how I read his post as well.

But I think what he is saying is that if you are at full braking and the car is in gear with the clutch engaged, you are using brake energy to slow the engine down. That is true although the effect would be negligible.

TeamRX8

iTrader: (25)

n00b alert!!!!!!

deamicls

iTrader: (1)

Wow....just wow.

EnzymaticRacer

That is close to what I meant, but not exactly. Which is why I quoted the post that I did.

Sorry if I didn't make that caveat more clear... engine braking + full brakes is slower than full brakes alone. is probably the best way to put it.

olddragger

iTrader: (3)

match rev--that is why you need a midpipe.
OD

olddragger

iTrader: (3)

and true what racer said
OD

Mawnee

While I always engine brake just out of habit. I dont believe doing such actually helps you slow down any faster.

Disable your ABS and your car can lock its brakes at any speed with ease. Nothing you do with your engine is going to allow you to slow down any faster than traction allows. Of course we all know locking the brakes isnt the fastest way to slow down, but the point is that your disc brakes are 'capable' of putting your roatating wheels to a dead stop at any time.
This isnt even taking into account that the drive wheels are on the rear of the car and the wheels taking most of the braking load are your fronts, hence the larger brakes up front.



edit- Sorry to boost this old thread. didnt realize I was still trawling threads from a search

climacus

Maybe I'm old school but I was always taught to let the clutch out as quick as possible and to make all the shifts as transparent as possible. It makes me cringe when I see people rock their car back and forth at a red light using their clutch.

CnnmnSchnpps

iTrader: (1)

I used to do this on my Civic. But that car weighted quite a bit less and the pedals were all wrong to even begin to learn the heel-toe. It also had no tach. And no power steering. God I love the 8...