Butler
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Registered: 2nd Jun 05
Location: London
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Is it possible to rev a car beyond the limiter by downshifting into 2nd by mistake from 5th. Some guy I know reckons his 1.4 Polo revved beyond about 10k and its still working. I was always under the impression that if the car had a limiter then this wouldnt be possible, and he told me to google 'mechanical over rev'
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johnboy-0178
USER UNDER INVESTIGATION - DO NOT TRADE
Registered: 28th Sep 10
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if its been dropped down from 5th to 2nd it more than likely fuked the engine by bending valves or snapping timing belt which both are very common
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Jake
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Registered: 24th Jan 05
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its possible yeh because its forced into over-revving. modern cars are electronically limited
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SnK
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Registered: 2nd Mar 09
Location: Yeadon, West Yorkshire
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I know some pratt who did this in his 1.4 polo. Was doing like 90mph shifted into 2nd instead of 4th. New engine.
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Phillips_91
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Registered: 20th Jan 10
Location: Blackpool. Drives: Sapphire Black Mk4 Astra 1.8
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i did it once by mistake only revved to just over 8k though so not too bad :/
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gavin18787
Premium Member
Registered: 22nd Feb 05
Location: Basildon, Essex
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Its possible yer
Not good for the engine at all. most modern cars record it in ECU's incase of warrenty claims.
Someone who works for honda posted up a reading of 15,000 on one car they had in for work on another forum 
Drives supercharged Tec with torque  
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Butler
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Registered: 2nd Jun 05
Location: London
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I always assumed the limiter prevented it from happening. Then again ive only ever done something so stupid on gran turismo
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DaveyLC
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Registered: 8th Oct 08
Location: Berkshire
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quote:
Originally posted by Butler
Is it possible to rev a car beyond the limiter by downshifting into 2nd by mistake from 5th. Some guy I know reckons his 1.4 Polo revved beyond about 10k and its still working. I was always under the impression that if the car had a limiter then this wouldnt be possible, and he told me to google 'mechanical over rev'
The rev limiter is in the ECU, how is the ECU going to stop the road turning the engine through the wheels?
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Ojc
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Registered: 14th Nov 00
Location: Reading: Drives : Clio 197
User status: Online
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Yes, in my early years of driving I was racing my mate in his 1.4 8v Astra Si and he went from 3rd to 1st and bent valves and all sorts.
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gavin18787
Premium Member
Registered: 22nd Feb 05
Location: Basildon, Essex
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There is a horrid video of a DC5 on youtube of it scattering parts on the track after someone decided to try 2nd at 4th speeds 
Drives supercharged Tec with torque
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Butler
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Registered: 2nd Jun 05
Location: London
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quote:
Originally posted by DaveyLC
quote:
Originally posted by Butler
Is it possible to rev a car beyond the limiter by downshifting into 2nd by mistake from 5th. Some guy I know reckons his 1.4 Polo revved beyond about 10k and its still working. I was always under the impression that if the car had a limiter then this wouldnt be possible, and he told me to google 'mechanical over rev'
The rev limiter is in the ECU, how is the ECU going to stop the road turning the engine through the wheels?
Yeah it makes sense when you put it like that. Ive never been particularly mechnically minded admittedly.
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Warren G
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Registered: 14th May 06
Location: Kent
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yes i know someone who went 2nd at 7500rpm to 1st...
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gavin18787
Premium Member
Registered: 22nd Feb 05
Location: Basildon, Essex
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Is it an anogram of A F D ?
Drives supercharged Tec with torque
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AlexW
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Registered: 25th Oct 08
Location: Essex
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This one gav? http://www.youtube.com/watch?v=BJQXlwr0H1A&NR=1
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richc
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Registered: 24th Mar 07
Location: Ilkeston
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My old corsa had a fucked gear linkage. I did 6700 rpm in second and hit first racing my mate in his mums 1.8 turbo passat when we was 17
Did do anything just sounded mental. Then a few weeks later a mate did same and blew it up! Sounded like a impreza
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Warren G
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Registered: 14th May 06
Location: Kent
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quote:
Originally posted by gavin18787
Is it an anogram of A F D ?
S Y E
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Rob B
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Registered: 8th Jan 04
Location: Area Motorsport Drives: Race EP3
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Happens alot on Honda's due to the close ratio box and the fact there all ready on the considered limit of vibration that the engine can withstand.
Spoon sports had to fit an engine brace to withstand a 10k rev limit.
And like Davey said, if you did it the ECU can't limit the speed the wheels are turning.
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Ian
Site Administrator
Registered: 28th Aug 99
Location: Liverpool
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I've seen it done, third back to second, got about 9 on an X14XE which lived to tell the tale.
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Warren G
Member
Registered: 14th May 06
Location: Kent
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mine lived with 8 new valves
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SportBoy
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Registered: 5th Oct 01
Location: Retford, Nottinghamshire
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i put my old xe in the wrong gear many moons ago racing an rs focus ... rev needle went past my airbag light and nearly back to the start .. dam thing still ran tho !
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Ingham
Banned
Registered: 9th May 08
Location: Burnley, Lancashire
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I went from 4th to 1st once but luckily didn't do any damage as dipped clutch straight away. 
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McWillster
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Registered: 23rd Mar 09
Location: Huntly, Aberdeenshire
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quote:
Originally posted by Ojc
Yes, in my early years of driving I was racing my mate in his 1.4 8v Astra Si and he went from 3rd to 1st and bent valves and all sorts.
How did he even manage that? Both gears are at the top The movement from 3rd to first whilst racing shouldn't even of entered his head. 
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Paul_J
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Registered: 6th Jun 02
Location: London
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quote:
Originally posted by Butler
I always assumed the limiter prevented it from happening. Then again ive only ever done something so stupid on gran turismo
Think what a rev limiter is?
... as you hit your rev limit, the fuel or spark is cut ... (controlled by ecu) this stops the engine revving higher.
Therefore, if you down shift from 5th to 2nd, then it will over rev (ok so the fuel and spark will not be happening) but the wheels, to transmission to engine will still be connected and cause the engine to rotate at the higher speed unless you dip the clutch to seperate the connection
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Ojc
Member
Registered: 14th Nov 00
Location: Reading: Drives : Clio 197
User status: Online
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quote:
Originally posted by McWillster
quote:
Originally posted by Ojc
Yes, in my early years of driving I was racing my mate in his 1.4 8v Astra Si and he went from 3rd to 1st and bent valves and all sorts.
How did he even manage that? Both gears are at the top The movement from 3rd to first whilst racing shouldn't even of entered his head.
The gearbox on his car was really stiff and hardwork anyway, and racing me and the fact he isn't that bright all were factors in his cars downfall.
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3CorsaMeal
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Registered: 11th Apr 02
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i'd done the 4th to 3rd, instead of 5th a few times, usually going a steady speed so i carry on in 3rd after making the mistake like i meant to do that
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