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Discussion Starter #1
...in the three months i've driven my elise, there've been probably two or three occasions where i've missed a downshift and accidentally overreved somewhere in the range of 8500-9500 RPM for half a second to a second...how much margin of safety do the engine and oil pump allow, and should i be worried about having seriously damaged anything?..
 

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My experience with old school GM motors is simple...the damage happens instantly or not at all. Metal fatigue is a complicated subject, though. If you didn't have an immediate problem, consider yourself lucky and be more careful.
 

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I think I had 3 between 8500-8700... result: valve broke and ended up chewing the bore in #1. Now I need a new motor.

A few people on monkey seem to think our motor should not exceed 8000rpm and that when you do you run the risk of floating a valve.

Furthermore, it's suggested that lots of the cam issues are caused by winding the **** out of the 2ZZ.

Next motor I'm having my motor limited to 8000 with a Charlie Tune.
 

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Discussion Starter #4
I think I had 3 between 8500-8700... result: valve broke and ended up chewing the bore in #1. Now I need a new motor. Furthermore, it's suggested that lots of the cam issues are caused by winding the **** out of the 2ZZ.
...eep - sounds like i should consider myself lucky indeed...
 

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They aren't monkey noobs.

We all, including the Lotus engineers, have a sense of where we would prefer the balance of performance versus reliability to be. It makes much more sense to assume that their idea of where that balance should be is in a slightly different place than where you think it should be.

xtn
 

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if you have a few revs over 9000 you would be considered VERY lucky to have it still running. Also it will not blow up on you immediately after. the valves will bend before they break.
 

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I rev mine to just shy of 8500 rpms daily. No issues, car runs very strong.
 

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Discussion Starter #10 (Edited)
if you have a few revs over 9000 you would be considered VERY lucky to have it still running. Also it will not blow up on you immediately after. the valves will bend before they break.
...at the moment it seems to be running fine, but considering that my most :crazyeyes overrev experience was yesterday, should i be concerned enough to take it in and have the head pulled for a visual inspection?..
 

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when mine blew it blew almost 3 laps after the overrev. That was at full tilt track driving with rev a little closer to 10k. Valve bent then a few laps of hard running it finally broke off. I'm not sure if it would take longer to fail in street driving or not. Did this happen on the track?
 

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I may be stating the obvious here, but no ECU tune is going to save you from a mechanical over-rev due to accidental downshift.
 

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Rev limiter anyone?
I don't believe it can it just cuts the ignition and/or fuel. But if the rev limiter value is set at something that can potentially damage an engine that’s asinine and poor engineering.
 

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a rev limiter will NOT save you from a misshift(mechanical) overrev!
A missed shift would fall in the neutral rev category the rev limiter should handle that, unless our cars don't have a neutral rev limiter. An actual downshift can overrev the engine
 

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a rev limiter will NOT save you from a misshift(mechanical) overrev!

I have misunderstood this for years then.

Please explain

Edit**
Ok, you are talking about the transmission spinning the engine, not your right foot.
 

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I have misunderstood this for years then.

Please explain
If your vehicle speed is fast enough that the lower gear you put the car into exceeds the rev limiter than when you down shift it your mechanically linking them. It will be a engine braking scenario, the ecu will cut the spark and/or fuel and the vehicle inertia will drive the engine the higher rotational speed as you will be slowing down. The excessive frictional force created by the engine will slow you down quickly but for the brief instance it will exceed the programmed restriction. Only applies to a manual transmission. Typically a rev limiter may have a different value depending on the gear your in (may even lack one when your in neutral) but it will prevent the engine being throttled to the higher speed.
 

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i think the 8500 is for those instances when you really need those extra 500rpms, say at a race in a track. i try to shift just shy of 8000 to preserve the engine.
 

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the exige S GT4 (a 270 hp version of the cup car) has it's limiter at 8250.
 
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