Overrev 2nd@redline into 1st

[dietdrk]

Well,

Out tooling around yesterday i tried to go from 2nd into 3rd. Of course the stupid thing is locked out (have recalled mount, and new brushigs) but anyway, i slip i guess and into first. let off the clutch and waaaamamamama

Car dives back down to lower speed.

It seems to act fine. I have been driving it since then (this happened sunday) and everything appears good with it.

I'm hesitant to take it to the dealer and tell them what happened. Im thinking about taking it to a local shop and seeing if they can take a kinda look at it, just for my peice of mind.

should i be worried?
Does this thing has a black box to tell them this has happend if i have problems 20k from now?


(2k ms3)

[Betelgeuse]

You shouldn't have anything to worry about as long as it's not too often. Many people have done the same thing with little consequence.

How are you holding the shifter? Try using your palm to nudge it into 3rd. It should just fall into place.

[dietdrk]

is it true about the black box?

I was at 6k in 2nd what does that translate into in 1st?

[Betelgeuse]

Yeah I believe rpms can be recorded but they usually don't go digging up that info unless they have reason to suspect abuse. Mistakes do happen. Plus I really don't know the length of time that data stays recorded. From what I gather about the airbag black box, is they record a certain amount of seconds before (and after?) a crash.

Here's an article on the black box:
http://money.cnn.com/2006/08/22/autos/edr_concerns/index.htm

[Frisco speed3]

You need to get a compression and leakdown test. If you were getting on it you could very well have bent a valve or damaged the valvetrain in some way. A little valve bend may not be noticeable on the butt dyno butt could lead to major issues down the road. It shouldn't be that expensive to get it done and will give you peace of mind.

[FrequentFlyer]

Nothing to worry about? I disagree. That's a mechanical overrev. There's lots of things to worry about in my opinion and it only takes one time. All depends on how strong the top end is, but you can bend valves and/or crack retainers. If you had a bent valve, you'd probably know already, but a cracked retainer may hang on for a while and not rear its ugly head until later on when it fails altogether and drops a valve down into a cylinder. I'm guessing you were somewhere around 7,500 RPM, but it's not really the RPM as much as the rate of change in RPM that damages the motor. I believe the ECU will store max RPM. For how long? I don't know. Sorry to scare you, but this happened to quite a few people in the S2000 forums when I owned one and even in a car designed to rev to 9,000 RPM, they'd find cracked retainers after mechanical overrevs. The only way to really tell is to pop the valve cover and inspect the top end, but that is a lot of work. You are kinda rolling the dice though continuing to drive it. I can't believe you got the thing into 1st gear at 6,000 RPM in 2nd.

[dietdrk]

yea ive hard horror storesi from a friend about moneyshifting.

Just wondering how much i have to worry about in this car.

Migh ttake it to get a compression test tomorrow see what they say.

[Betelgeuse]

yea ive hard horror storesi from a friend about moneyshifting.

Just wondering how much i have to worry about in this car.

Migh ttake it to get a compression test tomorrow see what they say.

RPMS matter but imo, the extent of damage depends on how fast you were going and what gears it occurred in. 2-1 isn't nearly as bad 4-1, 5-2 or 6-3 (like at highway speeds). I think the compression test is a good idea. But I wouldn't lose too much sleep over it unless you start smoking or there are obvious problems. If you suspect something or hear anything strange take it in (but remove any mods).

One member over on one the other forums autocrossed his car and shifted into first several times and so far have had no issues. Of course it's all at low speeds and usually 2nd to first. Also, it doesn't mean you won't have an issue because he didn't.

[User Name]

This brings up a good question, are these engines interference or non-interference engines? With a timing chain instead of a belt I have to believe it's an interference design, so nice with my 92 Miata to not have to worry about bending valves if the timing belt snaps.

[Betelgeuse]

From what I read, it is an interference engine.

[MicaSp33d]

This brings up a good question, are these engines interference or non-interference engines? With a timing chain instead of a belt I have to believe it's an interference design, so nice with my 92 Miata to not have to worry about bending valves if the timing belt snaps.


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.

[FrequentFlyer]

A compression test obviously won't hurt, but again, if you've got a damaged valve retainer, ie: stress cracks from an overrev, a compression test is not going to show that, but you will definitely know it when one lets go. The retainer is all that's keeping the valve from dropping down into the cylinder and I imagine if that happened, there'd be some "interference". :D

[speed_3]

From what I read, it is an interference engine.

i know the mazda b series motors are non interference motors

[jp4130]

The MZR is an interferance motor.

[mazdaspeedster3]

is it true about the black box?

I was at 6k in 2nd what does that translate into in 1st?

No offense but this does not happen on occasion. If it does you need a driving lesson. Your poor car man. Lock out is 6k RPM in second going to 1st. You would have had to CRAM that into gear in order to get it to go and it had to make a lot of noise getting there. Incredible. You didnt go through the windshield or hit your steering wheel? Wow... 3rd is not that hard of a shift even when stock. Sorry for going off but the more I read this the more I got over whelmed that this even happens.

[AutoXRacer]

1.6L and 1.8L Miata engines are non-interference... MZR engine is!!!

I wouldn't worry...besides, your car is still under warranty...if anything breaks later on, just take it in and act stupid.

I still don't understand how you got it into 1st...you must have really nailed that sucker into 1st. My 1st gear locks me out as soon as I'm in 2nd.

[phantom6294]

is it true about the black box?

I was at 6k in 2nd what does that translate into in 1st?

6k RPM in 2nd gear should be about 52 MPH... 52 MPH in 1st gear is about 9,500 RPM.

[AutoXRacer]

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

[robin2660]

No offense but this does not happen on occasion. If it does you need a driving lesson. Your poor car man. Lock out is 6k RPM in second going to 1st. You would have had to CRAM that into gear in order to get it to go and it had to make a lot of noise getting there. Incredible. You didnt go through the windshield or hit your steering wheel? Wow... 3rd is not that hard of a shift even when stock. Sorry for going off but the more I read this the more I got over whelmed that this even happens.

Your avatar is a perfect expression for your response.

[mazdaspeedster3]

Your avatar is a perfect expression for your response.

Thread Jack...

LOL... Thanks, that is how I felt when I was reading it. That is my 10 month old son, he is a clown for the camera.

[ZooZoom]

Everyone (except those who lie) has experienced a mis-shift. I doubt you actually hit the "theoretical" equivalent RPM's between gears at whatever speed (mph).

If your reaction was like mine, your right foot quickly engages the clutch when you realize (by feel mostly) things aren't going right.

I've probably mis-shifted 2 or 3 times. Car never behaved badly or acted weird afterwards. I've found the Mazda engineers really built the MS3 well and designed it for aggressive driving - and the occasional opps.

[mazdaspeedster3]

So those who lie have hit down shifts like this?

[thefrog1394]

Well second to first seems pretty insane. Maybe the MS3's are better with the 2 to 1 shift, but I have to double clutch to get my car into first if im rolling at all. Although I will admit to a couple near misfits going from 4 to 5 and accidently hitting 3 instead. Although Ive always caught it before the engine over revved. Its kinda hard not to notice the rpm's jumping way up and i kind of instinctively slam on the clutch before the engine redlines.

[ZooZoom]

I wasn't specifically talking about a 2-1 "upshift" here. Hell, I seriously doubt that's even possible at redline or close to it.

I'm talking about balls-out shifting on the fly when a 4-3 "upshift" might happen. That's the one that I've encounted a couple times on the track.

Like I said, your body tends to react even faster than your mind has time to realize a mis-shift occurred. When you feel the car reacting harshly your clutch foot should catch the engine before truly wicked high rpms occur, thus avoiding any damage.

at least that's how it works for me......

[mazdaspeedster3]

Well second to first seems pretty insane. Maybe the MS3's are better with the 2 to 1 shift, but I have to double clutch to get my car into first if im rolling at all. Although I will admit to a couple near misfits going from 4 to 5 and accidently hitting 3 instead. Although Ive always caught it before the engine over revved. Its kinda hard not to notice the rpm's jumping way up and i kind of instinctively slam on the clutch before the engine redlines.

Double clutch, please explain...

[Buyer]

Everyone (except those who lie) has experienced a mis-shift. I doubt you actually hit the "theoretical" equivalent RPM's between gears at whatever speed (mph).

If your reaction was like mine, your right foot quickly engages the clutch when you realize (by feel mostly) things aren't going right.

I've probably mis-shifted 2 or 3 times. Car never behaved badly or acted weird afterwards. I've found the Mazda engineers really built the MS3 well and designed it for aggressive driving - and the occasional opps.

You shift with your right foot??? I do agree with the mis-shift theory, but seriously 6k in 2nd to 1st is a completely moronic move...You would have to really try to get it into gear like that...

And no offense but who are you to judge whether mazda built a car well or designed for aggressive driving? Are you a race car driver or engineer? I mean come on dont the engines fall out of these things?

[phantom6294]

Double clutch, please explain...

Explain what double clutching is? Did I miss sarcasm? If not...

Normally used for downshifting to bring the engine to the necessary revs. Say you're in 6th gear cruising at 70 MPH and you want to go to 4th gear.
1. Clutch in
2. Shift to neutral
3. Clutch out
4. Bring RPM up to necessary level, in this case about 4200 RPM
5. Clutch in
6. Shift into lower gear
7. Clutch Out

In theory, you don't HAVE to use the clutch either time -- the first time because many cars can be forced out of gear without using the clutch, the second time, if you match the revs properly, it should slide in 'like butta.' It should be one fluid motion -- your clutch foot should in, out, in, out with maybe a little pause to get the RPM right.

Double clutching basically does the job of the synchros and if done right, eliminates wear on the pressure plate and clutch friction surfaces, but in theory, puts more wear on the throw out bearing since you're moving the clutch twice as much.

I taught myself to double clutch when I was 17 and been doing it ever since. It's now second nature when I go to downshift.

[mazdaspeedster3]

Can you not just blip or heel toe for the right RPM to mesh the Synchros? You dont need all that unecesary motion.

[phantom6294]

Can you not just blip or heel toe for the right RPM to mesh the Synchros? You dont need all that unecesary motion.

Yes and no. Bringing up the RPM while still in gear will bring the Clutch / Flywheel to matching speeds, but not the synchros. The sychros do that as you shift into the gear.

[thefrog1394]

The syncro's do their work even when the clutch is in. You have to actually let out the clutch in neutral and then rev the engine to eliminate the wear on the syncro's. Thus the reason its easier to double-clutch into first gear. The syncro, at least on my car, is a bitch on first gear. So I basically do the job for it by revving the engine up in neutral. But the key is that the clutch has to be out in neutral.

[FrequentFlyer]

Double clutch, please explain...

You step on the clutch, take it out of 2nd into neutral, release the clutch, step on the clutch again, throw it into 1st and release the clutch. That is double clutching. You're basically giving the syncro's enough time to react to the new gear.

[mckraut]

I also double clutch with just about every downshift.

[PCspeed3]

I still don't understand how you got it into 1st...you must have really nailed that sucker into 1st. My 1st gear locks me out as soon as I'm in 2nd.

Seriously, i try to get it into first from 10-15 mph to stop for stop signs occasionally and she wont let me go there. Starting off in 2nd from a stop sign (slow roll) wont hurt anything will it?

[phantom6294]

Seriously, i try to get it into first from 10-15 mph to stop for stop signs occasionally and she wont let me go there. Starting off in 2nd from a stop sign (slow roll) wont hurt anything will it?

Shouldn't... unless you're slipping the clutch a lot (clutch wear) or the engine shudders / lots of vibrations from being at too low of an RPM which would put stress on the motor mounts.

[mazdaspeedster3]

Are you guys driving late model vehicles? This has been remedied since the late 80's. Double clutching is something semi trucks dont even do any more when torque braking.

[mckraut]

Are you guys driving late model vehicles? This has been remedied since the late 80's. Double clutching is something semi trucks dont even do any more when torque braking.

I drive an MS3, just like my signature says.

If I can save some wear and tear on things by rev matching, you're damn right I will. Plus it's fun to confuse/impress people by not using the clutch pedal at all while driving (this I rarely do however).

[mazdaspeedster3]

I am talking 2nd to 1st shifts and double clutching. Rev matching and slipping shifts is easy but does wear on the synchros, no question.

[mckraut]

I am talking 2nd to 1st shifts and double clutching. Rev matching and slipping shifts is easy but does wear on the synchros, no question.

In that case, no, I never shift from 2nd into 1st at stops nor while parking.

You're saying rev matching wears on synchros? You mean saves them I think...

[mazdaspeedster3]

Shifting without the clutch by rev matching.

[thefrog1394]

I'm driving an 03 protege. And unless I'm going like 3 mph theres no way im gonna get the tranny into first without it putting up a fight. Most people don't even bother going into first at things like stop signs they just slip the clutch in second (i do that most of the time too). I just sometimes want to floor it from a rolling start, in which case I need to get into first to get some good acceleration.

[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.

[pdqgp]

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...