Quick, I don't mean to be a total DICK HEAD but ..........
Your not going to douche all four cylinders on a single free rev "overrev" .......... what's up with a missed shift and flooring it till the cows come home action? Was the clutch in or out when you were standing on the gas? Things ain't adding up here.

In any case, good luck getting it back on the road

 

RT, my right foot was quicker to get back on the gas before realizing I missed the gear, that's all. I don't know what the cause of it was, rev limiter didn't activate, loose plugs, who knows.

I just get more upset when I think about it so I'm just not going to, it's not worth it. The valves are bent, and they need to be replaced. Sucks big time for me. The car's in good hands at least...

 

If i'm not mistaken Con rods are meant to stretch a certain amount as the rpms rise.

If thats the case then the cylinder pressure will play a role in how much they stretch.

Under load the cylinder pressures are probably quite high. Under a free rev i bet they are significantly lower thus allowing for a greater stretch.

That would likely have the effect of lowering the Max rpm before overrev damage occurs.

I'm just thinking aloud here... does it make sense?

 

I think that jguerdat is on the right track.

My guess: The combination of a missed shift at redline while "on the gas" was too much for the rev limiter to keep up with. There was enough fuel in the pipeline (already scheduled) to over-rev the engine when the load was removed and not reapplied.

Denis

 

Does the ECU show a history of the overrev?

 

One thing I'm curious about is if this guy's car is stock. If he has a light weight flywheel, pressure plate, and pulleys, then the revs would climb much faster than the ECU would expect.

 

gernby, car is completely stock. Bill tried to pull the history of the overrev but as I remember it did not record anything until the car came back to idle.

It's being towed to Bill's on Saturday...

 

I thought that the ECU would save the previous X seconds of data (TPS, RPMs, Speed, etc.) when a major DTC occurs. I've heard of this data being pulled by dealers in the past (using the Honda specific scan tool) to prove overrevs.

 

soooooo.... a baseball pitcher throws a fast ball at 100 mph, did the ball leave his hand going slower than 100 mph and gain speed half way there ??????? .... oorrrrr did the ball leave his hand at the peak velocity and start slowing down the instant the accelerating force was removed?
For you Physics and Calculus buffs, RPM is speed, not position.

 

RT,

You are getting to be an ASS in your old age. I've spent several hundred hours over the last 13 months developing my own custom fuel controller, and calculating RPM is part of it (a difficult part). The ECU does not know what the RPM is until it can calculate it from the crank position sensor pulses. A single pulse is not adequate to determine RPM speed. You need AT LEAST 2 pulses. I know that this is an extreme case, but it is mathematically possible for the engine speed to accellerate from 1K RPMs to 10K RPMs in one combustion event, and the ECU would still think that it is spinning at 1K until it gets another RPM pulse.