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Ok, I'm an idiot

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Old Jun 5, 2007 | 08:29 AM
  #1  
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From: Blacksburg, VA
Ok, I'm an idiot

And apparently I haven't learned from my mistakes either.

For the second time I have downshifted into 2nd at a little too high of speed. Last night I was going about 60-62 mph and thought 3rd gear wasn't good enough and decided to go into 2nd gear. Well, I don't know if I thought I was going a little slower, but when I started to let the clutch out the rpms shot up to about 9k and were up to about 9.5k or 9.6k rpm very briefly before I put the clutch back in. The clutch was not even fully released for more than a split second before I realized what was going on and I immediately upshifted.

Everything seems to be normal, but...aside from a completely blown engine, what would the signs of overreving damage be? We all know the rotary likes high rpm, but how would you know if you had overreved it and caused damage?
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Old Jun 5, 2007 | 08:44 AM
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From: Houston
Originally Posted by Rhythmic
how would you know if you had overreved it and caused damage?
You'd know by posting a thread about the topic...

Also, I've dropped it into 2nd at 60... Shift at 65... The actual rotors go a third the speed of the shaft so once you think about it, it's not as freaky dinky fast as I thought it always was
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Old Jun 5, 2007 | 09:33 AM
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^ so, your engine was not damaged I take it (as far as you know)?
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Old Jun 5, 2007 | 09:37 AM
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.
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Old Jun 5, 2007 | 09:42 AM
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Don't feel bad, you're not alone on this...

I've done this very same thing on 2 different occasions. For me, it was a miss on the 5-6 shift. Both times I meant to upshift and ended up downshifting to 4th. Now, I'm EXTRA careful on this...
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Old Jun 5, 2007 | 12:25 PM
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60-62 HAHA I hit 69-70mph in 2nd.

http://www.youtube.com/watch?v=5cFWDJlRoAo
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Old Jun 5, 2007 | 12:47 PM
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Yeah, but on the RB flash. Very cool though.

Everything seems to be normal with my 8 post-dumbass move. I will permanently imprint "<60mph in 2nd" into my brain. But I'm going to assume that 9.6k rpm from my ill-advised downshift has not harmed my baby (with stock flash). Maybe my clutch suffered more of the abuse than the engine?

I am still wondering how you can tell if any damage has been done. Compression test? Should I just not worry like an OCD chauncey?

I don't think I used enough smilies...

Last edited by Rhythmic; Jun 5, 2007 at 12:49 PM.
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Old Jun 5, 2007 | 12:56 PM
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I downshift once couple days ago and my rpm shoot way off the 10K rpm mark.

but I revmatch it correctly so not much *shaky* feel.

ur engine is fine. tranny should be ok too, not like u doing it often.
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Old Jun 5, 2007 | 01:00 PM
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The car will get fuel cut on the stock pcm. Besides if my car can do it, I dont see how your car would get hurt. I dont have any special clutch or tranny, just a flash that lets me do stupid things.
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Old Jun 5, 2007 | 02:24 PM
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From: Blacksburg, VA
Originally Posted by nycgps
I downshift once couple days ago and my rpm shoot way off the 10K rpm mark.

but I revmatch it correctly so not much *shaky* feel.

ur engine is fine. tranny should be ok too, not like u doing it often.

Holy sh*t. 10K+ rpm on a downshift! Wow. How fast and what gear?

what do you mean "shaky" feel?

Well, I guess I'm not alone anyway...I feel so much better now I'm sure I'm not the only one that obsesses over their car either.
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Old Jun 5, 2007 | 02:49 PM
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when im on a track, i do that alot!
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Old Jun 5, 2007 | 05:12 PM
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you likely have no damage based on your description of the conditions, you'd need to be at a much higher speed than that for 2nd gear to have a problem
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Old Jun 5, 2007 | 05:23 PM
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From: everywherez...
I'm surprised you got into 2nd at all...but then again perhaps your syncro isnt as messed up as mine is...
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Old Jun 5, 2007 | 05:28 PM
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Never downshifted to 2nd at that speed, but I routinely shift from 2nd to 3rd at around 65mph. I wouldn't recommend downshifting to that gear......... at that speed, but shouldn't be any damage to your car.
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Old Jun 5, 2007 | 05:51 PM
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i know the synchros in 3rd gear dont give out as easy as second... but i've downshifted into 3rd at well over 100. by my judgements, i prolly hit somewhere around 11-11,500 rpms for a split second. only did it once, and another time that wasnt as bad. no probs for me.
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Old Jun 6, 2007 | 08:45 AM
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From: Blacksburg, VA
Originally Posted by TeamRX8
you likely have no damage based on your description of the conditions, you'd need to be at a much higher speed than that for 2nd gear to have a problem

What estimated speed would cause damage in 2nd? Just wondering, I won't dare to see for my self. I know you run at high rpm a lot in your autocross events Team.
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Old Jun 6, 2007 | 09:02 AM
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I dropped my car into 2nd instead of 4th at over 100mph once. the tach goes past 10k. it's funny because if I shift out of first and into second near redline it almost always grinds, but shifting from 3rd into second was buttery smooth, until the fuel cut and my subsequent freaking out for a second.
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Old Jun 6, 2007 | 09:28 AM
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Damn Aseras, that is crazy...and you haven't noticed any ill affects? sweet baby Jesus!
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Old Jun 7, 2007 | 01:08 PM
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It's always tried to grind 2nd since I bought the car new. The afss ( short shifter ) made it better. I dropped in into 2nd ( the 100mph bit ) @ 20k miles, I've got 64K miles now and it's running great.
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Old Jun 7, 2007 | 01:35 PM
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Originally Posted by Rhythmic
I am still wondering how you can tell if any damage has been done. Compression test? Should I just not worry like an OCD chauncey?
Depends on how obsessive you want to be

well-adjusted: - does it still run good? Yes? It's fine.

slightly obsessed: - compression check

mildly obsessed: - change the oil and get a used oil analysis for wear metals (Iron and Copper and Zinc! Oh My!)

moderately obsessed: - compare dyno results to your last 3 sets

Obsessive-Compulsive: - teardown engine to check the tolerances


In the scheme of things, 9.6 for a split second isn't too crazy. Should be avoided, but wouldn't worry that much. Fuel limiter cuts in over 9K (I've heard ) and surely that still provides a margin of protection, so your 9.6 excursion was only slightly out of bounds.
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