My friend was driving his car hard....while trying to shift into 3rd he went into FIRST GEAR and the car over-revved to 9k....why did the rev limiter not kick in???

Can this cause a lot of damage? because its the 2nd time it has happend...the car jumped for a second and the tires chirped when it happend....

 

The rev limiter can't stop that from happening if you shift like that.

 

hopefully your friend drives a POS cus he most likely screwed something up...

 

Nah... ive done that ONCE! and my car still running strong. I think just as long as your not on gas or have any load on the engine it should be ok.

 

Please tell me this wasn't an Evo.

 

i would check for stuff like bent valves and such

 

I Agree.

 

it can happen because it is a mechanical event. the rev limiter stops the engine from spinning electrically (by limiting the circuit) but in a downshift it is mechanical, meaning the gearbox ratios force the engine to those rpms, nothing can stop that but the driver

 

YES...it was an evo....

how would you know if a valve was bent?

 

the car runs like crap with bent valves.

A limiter can't prevent mechanical over-revving, on by applicaiton of fuel.

the only limiting factor is the rods and the vavletrain, and if it was a quick spike and he pushed the clutch in there should be no problem, just be more careful next time.

 

2nd time it happened? someone needs to slow down their shifting or learn to drive.

 

+ 5 to that

 

Agreed. The biggest danger with most cars is valve float, i.e. the cam is moving so fast that it slings the valve open with more force than the valvespring can contain, thus the valve may still be open when the piston moves up.

Missing a shift like that is REALLY bad in a Honda S2000 (especially the older ones). 9K rpm redline... ouch!

 

My friend just called me....he just drove his car for the 1st time after he over-revved it last night. He drove around the block a few times and he said it seemed normal. He didnt really drive it hard though so i wouldnt know if anything is messed up...

 

Sounds ok to me. If it were damaged, it would be impossible not to notice. It would run like crap even at idle (if it was able to idle at all).