Overrev 2nd@redline into 1st

[mckraut]

Shifting without the clutch by rev matching.

You sure? Because like phantom, I was under the impression that you're doing the job of the synchros.

Edit: Oops, I re-read what phantom said, he was talking specifically about double clutching, not clutchless shifting.

 

[AutoXRacer]

Umm, double clutching is no longer needed with new cars...that was back in the pre-80s era...

I keep getting flashbacks of the movie Fast and The Furious when Vin Diesel is lecturing Brian about not double clutching...um, yeah, we're in the 21 century... HELLO...?

If you are doing it because you're used to it, thats one thing...but its no longer standard practice... Look at race car driver's foot work next time, they don't double clutch...

Just my 0.02 cents.

 

[mckraut]

So you guys are telling me that there is no extra wear and tear on my engine parts if I drop down a gear or 2, just pop the clutch and let my RPMs sky rocket?

P.S. I'm really not trying to be argumentative, I really do want to know.

 

[controlo]

^ yeah man. i always rev match when i downshift.

i consider it especially necessary in a high compression motor like a k20.

 

[mckraut]

^ yeah man. i always rev match when i downshift.

i consider it especially necessary in a high compression motor like a k20.

Call me crazy, but it just feels better to me. If it truly does nothing with modern cars, so be it. But I'll probably still continue to do it just because I have for so long already.

 

[60181]

Personally, I'd never just pop the clutch. Can't see why anyone would. IMO, weather you go up or down gears, you should always try and rev match. If not for anything else, think of your passengers and those around you thinking you're a fool for bouncing around like a nut.

I've not followed the thread 100% but I tend not to slow down using the tranny. IMO, brakes are cheaper and I drive much smoother by simply putting the car in Nuetral as I come to a light and applying the brakes. If the light changes, I simply select the gear that's appropriate, rev to match my speed and slowly let off the clutch. No head-bobbing in my ride. Occasionally, I'll be slowing down, shift to second, rev higher and take off to keep the guy next to me from passing, etc...but that's when I'm feeling a bit spirited.

So you guys are telling me that there is no extra wear and tear on my engine parts if I drop down a gear or 2, just pop the clutch and let my RPMs sky rocket?

P.S. I'm really not trying to be argumentative, I really do want to know.

 

[TropicalDelight]

Oh and there is 60 seconds worth of data stored in the black box.

no it doesn't, the only time the PCM stores info is a freeze frame of when a DTC is stored.

 

[PCspeed3]

Rev matching may make your clutch last a week longer in the long run. I dont think its worth it to have to rev match every downshift.

 

[phantom6294]

So you guys are telling me that there is no extra wear and tear on my engine parts if I drop down a gear or 2, just pop the clutch and let my RPMs sky rocket?

P.S. I'm really not trying to be argumentative, I really do want to know.

Double clutching isn't really necessary as we do have synchros which do their job very well. I'm not aware of the average life span on the synchros in our trannys, but I've rarely heard about synchro failure in any car I've personally driven -- as such, I can't imagine double clutching is ever really going to noticably extend the life of the synchros.

As far as rev matching... if you don't do that, and just pop into a lower gear, then bring the clutch out... you're going to sacrifice the clutch to get the engine up to speed for the lower gear, assuming of course you let the clutch out slowly. If you let the clutch out fast, perhaps a bit less stress on the clutch but more stress on the motor mounts as they take some of the shock of the engine being suddenly brought up to speed. In either a case, you are putting more wear and tear on the clutch or motor mounts... as for the engine itself... I wouldn't think so.

So, at the very least... I would say always try and rev match, even if you aren't perfect, being 200 RPM off is better than 2000 RPM.

 

[dietdrk]

Well car seems fine.

I was on it at the time kidna heat of the moment and its hard to get into 3rd, i beleive I hit it felt lockout and tried to push it in, and then slipped into first, I was back on the clutch in probably less then a second.

 

[mckraut]

Double clutching isn't really necessary as we do have synchros which do their job very well. I'm not aware of the average life span on the synchros in our trannys, but I've rarely heard about synchro failure in any car I've personally driven -- as such, I can't imagine double clutching is ever really going to noticably extend the life of the synchros.

As far as rev matching... if you don't do that, and just pop into a lower gear, then bring the clutch out... you're going to sacrifice the clutch to get the engine up to speed for the lower gear, assuming of course you let the clutch out slowly. If you let the clutch out fast, perhaps a bit less stress on the clutch but more stress on the motor mounts as they take some of the shock of the engine being suddenly brought up to speed. In either a case, you are putting more wear and tear on the clutch or motor mounts... as for the engine itself... I wouldn't think so.

So, at the very least... I would say always try and rev match, even if you aren't perfect, being 200 RPM off is better than 2000 RPM.

Thank you. So , double clutching = not really necessary. Rev matching = a good idea.

I believe I somehow put the two practices in the same bucket, when in fact they're pretty different. Things like this make me realize how much I have yet to learn about cars. Thanks again.

 

[08_MS3_GT]

rev matching when downshifting is KEY. much better for the clutch.

as far as mis-shifting into a lower gear - i've done it (but not with this car), but i've always seen the rev's jumping up and engage the clutch before the gear fully engages.

a fully-engaged mis-shift from redline in a higher gear can blow the s*** out of your engine. can, not will.

 

[MicaSp33d]

Rev matching may make your clutch last a week longer in the long run. I dont think its worth it to have to rev match every downshift.

if you plan to downshift ... you will need to rev match .. upshifting is a different story.

try going through a corner .. you don't even have to go fast ... and downshift without revmatching ... the car becomes very unsettled.

rev matching = getting the down gear to equal the same speed as the last gear, if you don't, you will get instant engine brake which will upset the engine and suspension ... not good if going through mid corner ..

 

[jjjxlr8]

i guess its not always true, i snapped my timing belt in my civic and it bent 4 valves. I didn't even miss shift ... i was going from 4th to 3rd and it just snapped. Found out after it some cheap china belt the original owner put in.

It's all that carbon build up on top of the pistons!

 

[tiagotiago]

if you plan to downshift ... you will need to rev match .. upshifting is a different story.

try going through a corner .. you don't even have to go fast ... and downshift without revmatching ... the car becomes very unsettled.

rev matching = getting the down gear to equal the same speed as the last gear, if you don't, you will get instant engine brake which will upset the engine and suspension ... not good if going through mid corner ..

+1

Like any other reflex you end up doing it by second nature, so I usually end up rev matching most of my downshifts, even if I do it badly when I'm not really on it, or at a stupidly slow speed.

And tough I very rarely do double clutching, I don't see a problem with someone taking the time to do it. You're doing something to take care of your car's more expensive components so that shouldn't be a problem, even if it is no longer really necessary.

...and returning to the OP good thing your engine feels ok! I've missed some shifts before, but only once when going full chat (and that was in my first car) and nothing bad happened that time, that car is still plodding along.

 

[mazdaspeedster3]

rev matching = getting the down gear to equal the same speed as the last gear, if you don't, you will get instant engine brake which will upset the engine and suspension ... not good if going through mid corner ..[/QUOTE]

Just because you bring up the RPM's to match the synchro into gear once you let that clutch out in the down gear you are still only moving at that pace and are going to have the engine braking regardless... Your assessment isnt doing anything other than allowing you to go into gear easier, nothing more...