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Mis-shifts causing a blown engine?

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Old Aug 4, 2007 | 07:42 PM
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Mis-shifts causing a blown engine?

Haven't seen any posts here about this, but are mis-shifts causing a blown engine a risk? For example, shifting from 6th gear to 2nd when you really wanted 4th.
 
Old Aug 4, 2007 | 07:43 PM
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Yes, that's very possible
 
Old Aug 4, 2007 | 07:49 PM
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not common here because 6speeders know how to shift properly
 
Old Aug 4, 2007 | 07:53 PM
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It is in any manual car, it's called an over rev and your onboard computer tracks them.
 
Old Aug 4, 2007 | 08:13 PM
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Originally Posted by turbonator
Haven't seen any posts here about this, but are mis-shifts causing a blown engine a risk? For example, shifting from 6th gear to 2nd when you really wanted 4th.
Called a mechanical over-rev-
Probably the most common way to blow an engine...
 
Old Aug 4, 2007 | 09:08 PM
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This is what you call a over-rev. DHinkle is real good at doing this in his cupcar, just ask him.
 
Old Aug 4, 2007 | 09:21 PM
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the revs will shoot through the roof (as well as a piston) and "rev limiters" cannot stop that.

Originally Posted by turbonator
Haven't seen any posts here about this, but are mis-shifts causing a blown engine a risk? For example, shifting from 6th gear to 2nd when you really wanted 4th.
 
Old Aug 5, 2007 | 01:08 AM
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A mechanical over rev like on a down shift can and will damage an engine.

A over-rev on an upshift will generally not damage an engine since the car has a rev limiter..


 
Old Aug 5, 2007 | 06:58 AM
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Originally Posted by Confused
the revs will shoot through the roof (as well as a piston) and "rev limiters" cannot stop that.
Hmm... now if it weren't a flat six I'd agree with you, but yeah...



Just busting your *****
 
Old Aug 5, 2007 | 08:42 AM
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Bank shot!

Originally Posted by Origyns 973
Hmm... now if it weren't a flat six I'd agree with you, but yeah...



Just busting your *****
 
Old Aug 5, 2007 | 08:46 AM
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Though not on a turbo model, I've seen a connecting rod go into the starter.....
 

Last edited by porschespeeddemon; Aug 5, 2007 at 08:58 AM.
Old Aug 5, 2007 | 09:48 AM
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I am rebuilding a TT motor right now from that. We call it the 4-1 money shift
 
Old Aug 5, 2007 | 09:50 AM
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Originally Posted by PorschePhd
I am rebuilding a TT motor right now from that. We call it the 4-1 money shift
Pics of destruction?

 
Old Aug 5, 2007 | 09:53 AM
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I've heard that on certain cars (Corvette?, Viper?) the synchros on the tranny won't allow one to shift into a mechanical over-rev situation...don't know if this is true or not.

Would ordering the factory ssk make a mis-shift more likely, particularly in high adrenaline situations like on a track?
 
Old Aug 5, 2007 | 10:27 AM
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No the syncros can't stop a mis shift, never heard of this. The SSK wouldn't really have any direct effect, this is an operator error.
 


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