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Discussion Starter #1
I'm a little worried about my engine as a couple of weeks ago while racing a honda i hit a bad shift. I shifted from 5th @ 6000rpm down to 4th instead of 6th, as expecting i revs shot up to the limiter, i very very quickly dipped the clutch and stuck it into 6th.

Any chance of damage being caused by this? I was in 4th no more than a couple of seconds before i shifted it into 6th.

On a side note, this was a UK Honda Civic about 10 years old, clearly modified and was very very very rapid under acceleration, gave me a lot more trouble than it should have, even if i had 3 passengers (2 of which were fat b*stards lol) and he was on his own.
 

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I shouldn't think it would cause any problems - the rev limiter is there to stop any damage to the engine through over-revving.

Oh, and tuned Jap cars can be quick!
 

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do a search for "money shift" and read why this is so bad...
 

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I shouldn't think it would cause any problems - the rev limiter is there to stop any damage to the engine through over-revving.

Oh, and tuned Jap cars can be quick!
There is no rev limiter when down-shifting. There's a reason it's called "the money shift". But for a brief moment you're probably fine.
 

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If it was in 4th for 'seconds' as you stated, your car wouldn't be running anymore. If you didn't notice anything weird (vibrations, smoke, etc...) you might be ok. If so, you are very lucky.
 

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Let's see, 5th gear 6000 rpms, that's around 140-150 mph. I hope that civic was a distant speck in your rear view.:):M5launch:
 

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Yeah, I doubt it was a couple of seconds. It was probably more like hundreths of seconds.


Let us know if it goes haywire in the coming weeks. Prob. won't though if you caught it quickly. GL
 

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Might want to get an oil analysis to see if there is any bearing material coming off now.

If you catch it in time, its much cheaper to replace the bearings...
 

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If I were worried, I'd pull her up next to a brick wall, open my window, and slowly rev the engine up and down listening carefully for any sounds from the bottom end. Engine harmonics are such that any looseness will likely reveal itself. If a bearing is spun, you'll hear it.

Odds are everything is fine from a short excursion in the red. :)

Dave
 

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I'm not sure what the big deal is, given that 6k in 5th translated to 7.4k rpm in 4th. Dinan chip raises rev limit to 7250. TMZ raises it to 7400. I don't think those engines are getting damaged.
 

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How far back was the Honda?
 

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Discussion Starter #13
The rev's may have just kissed the red zone on the tacho before i re-shifted. They definately weren't into the red.

The honda was right next to me when i did this, although the misshift actually got me ahead, and then once i did the shift properly it was bye bye honda. The reason he was up next to me was that he had a huge run up on me, but i was still surprised that i couldn't pull away as quick as i thought i should.

And come to think of it, i think it was a 4th to 5th shift, that went into 3rd. Coz the speeds at 6krpm in 5th would have been way too scary for the road i was on!! And my passengers would have soiled their pants, and my girlfriend would have killed me, even though she was spotting for me, showing me gaps and lanes to be in lol!!

The car's in at the dealer tommorow for an inspection 2, so i'll mention the the bad shift and ask them to check the max rev's from the DME if they can. Will a dealer analyse the oil for you as well??
 

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A little less than a year ago, I misshifted too... I was in 6th, and wanted to downshift to 4th, to end up at 5.5K rpm. I hit 2nd instead of 4th :hihi: I noticed it immediately ofcourse, and pressed the clutch pedal quickly. Except that I lost the race, nothing bad happened :thumbsup:
 

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If there was a problem, It would have happened instantly!!! So you're OKAY!

Try not to ever do it again though!
 

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And come to think of it, i think it was a 4th to 5th shift, that went into 3rd. Coz the speeds at 6krpm in 5th would have been way too scary for the road i was on!!

The car's in at the dealer tommorow for an inspection 2, so i'll mention the the bad shift and ask them to check the max rev's from the DME if they can. Will a dealer analyse the oil for you as well??

First off, it is hard to believe you couldn't remember which gear you were in. There is a pretty big difference in going 5th to 4th, vs 4th to 3rd. :confused2

But having said that, a kiss at or slightly above the redline once like that shouldn't hurt anything. The engine actually pulls pretty good past 7300 and will easily pull to 7600.

I am not sure I would ask the dealer to read the DME. Something about letting sleeping dogs lie.......:cool:
Regards,
Jerry
 

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I agree with Jerry here. Because if you have the dealer pull the max revs from the DME, then the Service Advior will put that in as notes on your customer profile. If something should happen in the future they will say that you are at fault and that BMW will not assist you. Not that your vehicle is subject to any type of powertrain warranty any longer anyway, I am sure. Sooo... be very careful about whom you are breathing these words to. You just may end up very sorry...
 

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Discussion Starter #18
Advice noted. Didn't mention this to the dealership.

Also the fact that i didn't go into the red zone suggests that i probably didn't do any damage to the engine.
 

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So no damage usually occurs when you smack the rev limiter...only when downshifting do you get that magical "money shift" to where it tears apart the engine?? Just checking. :hihi:
 

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Yes, that shift is called the money shift. The downshift when you are doing 110 MPH from 5th gear to second, thinking you are hitting 4th is the Money Shift. And to those of you that may try to catch me in a technicality for the speed that I used, it is merely for the purpose of an analogy. This is only riding on the assumption that if you are going that fast and happened to downshift to second, it would happen.

Me personally, I never want to experience this. I had a friend that owned old Saab SPGs. He was well into the higher spectrum of the RPM band and he attempted a downshift from 5th to 4th and ate crow. You never heard a noise so loud in your life. Between the cloud of smoke, hard vehicle shudder and shrapnel spitting everywhere, we know that he didn't hit the right gear.

Any guesses as to which gear he slammed it into? Oh yeah, 2nd gear is the one. Foolish, foolish boy. I think what ends up happening is people aren't as familiar with their vehicles as they are to claim they were.

This is why bad downshifts happen, engines and transmissions become blown and drivers start blaming the "stupid vehicle". It's alright to power through the gears, but knowing your vehicle and the gear box certainly makes a difference. Try regular around town driving before like this.

But I can guess that if you get a little hot and bothered and some urge sets in to take the ricer kid along side you, some adrenaline, testosterone and stupidity start flowing through the veins. That's probably why a shift is missed... Just a guess.
 
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