oh really? i don't know if i shifted into reverse. i didn't let the clutch out - right after i shifted, i was like wtf? did i just shift into reverse? and then just got it back into neutral then into 6th. i don't know and i don't want to try again!

 

but w/ a stock ecu - it wouldve really mattered?... i mean, the most harm wouldve been your conscience!..i can see if you had a reproggramed ecu w/ no rev limit, then you'd worry about valvetrain ( retainers / springs..and so forth ) anyways - luckily you didnt get spokked or noone was behind you - james

 

Yes the ECU has a fuel cut but it takes more than an instant to kick in and the car can't exactly figure out what you are going to do BEFORE you do it.

There is still the chance of way over-revving the car if you downshift into the wrong gear.

 

Dude, chill out.

You almost mis-shifted.... whats the big deal? Im assuming you're new to MT vehicles. I've miss shifts alot of times at redline, mostly at the track.
Nothing happens to the vehicle if you know how to react.

Man, if you're so paranoid about missing shifts, try not to think about grinding a gear!

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i believe the fuel cut and the rev limit are 2 different things. revlimiter stops you from over-revving the motor, the fuel cut is more for the speed governor ( no - not arnold )

 

IIRC, the ECU will cut the fuel if you continue to hit the rev limiter or in an extreme condition. I may well be wrong about that but I believe that is the case. Regardless, even the rev limiter can't think ahead of you and when you are talking about 7K+ RPMinute then it doesn't take long to cause a problem.

 

Definately wrong.

Rev Limiter cuts the fuel so your engine won't over rev and blow up.

Fuel cut has nothing to do with the speed governor; that's more of an ECU thing

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that makes no sense -
this will just go back and forth
fuel would not be cut and your motor will not turn off when it hits revlimit ( you stated you ran at the track ) if that was true - you'd know all you would do is bounce off the limiter ( ive done it w/ nissans - ive done it w/ other cars ) the car hesitates for a moment - this is due to a combination of timing / fuel ( if you read trey's wife's post ) i believe she was under the impression redlining was all about fuel - that is incorrect.
heres apassage - anyone want to disput this, please search yourselves as well:
"At a pre-set rpm - say 7,000 rpm - the rev-limiter engages sometimes scaring the very cool driver half to death!! : Once the engine reaches 7,000 rpm, it interrupts the signal to the coil, alternating on/off, slowing the firing sequence"

this was from teamwest-tec.com ( or just google )
the fuel cut off affects the speed governor more so than in the rev-limit. ( which is why if you hit a certain speed, your car shuts off..coasts then restarts ) yes - while driving.

 

i'm not too sure about the " ECU will cut off the fuel if you continue to hit the rev limit " - this may be true, i was talking about hitting the revlimit accidentally, not keeping the motor bouncing off the limiter. also - aftermarket ignition systems have 2 stage systems ( for launching ) used for track and street racing as well - w/ the ebrake up, you can stage you car ( keeping the rev's to a desired rpm -
once released, you can drive you car normally ( through the gears redlining @ wherever you select the redline to be )

 

I do not know how you managed to do that?

 

I have never mis-shifted into a lower gear before. I have just mis-shifted at the race track in my old car. I'm not new to MT, all my cars I have owned except my work truck have been MT. I'm just informing people that it can happen and to be careful.

 

How does my post make no sense?

The rev limiter on a car is there to prevent over-reving, which will destroy the engine. If it over revs, it cuts the fuel which is why it keeps on boucing off the redline... it cuts the fuel, but bounces back because the driver has still given it more fuel.

And the rev-limiter has nothing to do with the speed governer. It's an ECU thing. You can take your ECU to a place such as Technosquare; they reflash your ECU which will REMOVE the speed limit (speed governer) and give you a higher redline.

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It IS true-the ECU is preprogrammed to cut the fuel if you continue to hit the rev limiter.

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d efinately wrong.

Rev Limiter cuts the fuel so your engine won't over rev and blow up.

Fuel cut has nothing to do with the speed governor; that's more of an ECU thing

reread you prior post -
1. rev limit doesnt cut the fuel, it DOES keep the motor from over revving, but this is via ECU.
2. fuel cut and speed governor work almost hand in hand ( more so in this case than w/ rev limit ) once youve hit max speed - your car will shut off ( for a quick second - then regain rpm's and continue to work )
youre right though - fuel cut is more of an ECU issue - but so is the speed gov.

* anyways, the point of the thread was that he almost mis-shifted, i was pointing out the fact that he was better off having a stock ecu than a reprogrammed ecu - he may have floated a valve and either damaged the head or the block *

 

Just for clarification, the revlimit functions by way of a fuel cut. They are not the same thing, but when the revlimit threshold is met, the ecu issues a fuel cut. The revlimit is a condition, and the fuel cut is an action.

From page EC-25 of the FSM:
Fuel to each cylinder is cut off during deceleration, operation of the engine at excessively high speeds or operation
of the vehicle at excessively high speeds.

So - that means that the fuel cut function in the case of rev limiter and the speed governor.

And I would like to reiterate: overrevving a car is still possible when one mistakenly downshifts at high rpms. That action is is a mechanical condition which the ecu cannot correct.