Over rev, bent valves, miss shifts
10-07-2003, 07:21 PM
#11
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my worst miss shift was when I tried to down shift from 5th to 4th and hit 2nd about 1.5 months ago. I caught it very quickly though. Although my car is in the car for bent valves right now so it may have not been quick enough. I didn't have any problems right away but in the last few weeks my car starts really crappy. It's like it sputters or something, is that the valves cause I don't know about these things. Hondas also saying that my warrenty may not cover it because they may consider it "abuse" after they look at it.
10-07-2003, 08:27 PM
#13
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most likely, the overrev bent the valves. Another thing about overrev is that the damage may not be apparent for a while. There is a piecce on the valve that will get a stress fracture with overrev. The engine will continue to run fine for awhile. But, when you start running it hard, the valve will go. Honda thinks this is the reason behind the mysterious #4 failure.
10-08-2003, 06:36 AM
#14
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If you have to mis-shift, miss on the way up 
As posted above, it only takes on revolution at the critical engine speed for valves to hit the piston. Assuming 10k is the limit, and you mis-shift into second gear at 75 mph (120 kph) you have 0.006 seconds to get the clutch back in.
Typical reaction times in humans are around 0.5 seconds. That's 83 turns of the engine.
To make matters worse, with the speed of sound at 330 metres per second, and the engine 2 metres away - the sound won't arrive before the engine is lunched.
EDIT:
checked the problem - of course it doesn't matter what speed you're doing, just the engine speed.
As posted above, it only takes on revolution at the critical engine speed for valves to hit the piston. Assuming 10k is the limit, and you mis-shift into second gear at 75 mph (120 kph) you have 0.006 seconds to get the clutch back in.
Typical reaction times in humans are around 0.5 seconds. That's 83 turns of the engine.
To make matters worse, with the speed of sound at 330 metres per second, and the engine 2 metres away - the sound won't arrive before the engine is lunched.
EDIT:
checked the problem - of course it doesn't matter what speed you're doing, just the engine speed.
10-08-2003, 09:15 AM
#15
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[QUOTE]Originally posted by Colin Andrews
If you have to mis-shift, miss on the way up
As posted above, it only takes on revolution at the critical engine speed for valves to hit the piston. Assuming 10k is the limit, and you mis-shift into second gear at 75 mph (120 kph) you have 0.006 seconds to get the clutch back in.
Typical reaction times in humans are around 0.5 seconds. That's 83 turns of the engine.
To make matters worse, with the speed of sound at 330 metres per second, and the engine 2 metres away - the sound won't arrive before the engine is lunched.
EDIT:
If you have to mis-shift, miss on the way up
As posted above, it only takes on revolution at the critical engine speed for valves to hit the piston. Assuming 10k is the limit, and you mis-shift into second gear at 75 mph (120 kph) you have 0.006 seconds to get the clutch back in.
Typical reaction times in humans are around 0.5 seconds. That's 83 turns of the engine.
To make matters worse, with the speed of sound at 330 metres per second, and the engine 2 metres away - the sound won't arrive before the engine is lunched.
EDIT:
10-10-2003, 03:49 PM
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I've been asking around lately and everyone I work with says pretty much the same thing, "Wouldn't the rev limiter kick in and not allow it to get that high of rpms?" Well, would it or not? In the last week I recieved a phone call from the Honda dealer saying that they would not cover my 8 bent valves with my warrenty. I have the extended 100k mile power train warrenty and the car has 43k. Then I bitched at them and the guy I talked to said he would call the warrenty company to send an investigator to look in person. I will not find out the results of that untill Monday. If they still won't cover it I am going to take it to Honda themselves and complain. Do I have a case or not? In my opinion it should be covered under warrenty, am I wrong?
10-10-2003, 04:03 PM
#18
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if it turns out that I have to foot the bill I may consider buying stronger valves, if there is such a thing. Are there better valves and certain thing that are resonabley priced or no?
10-10-2003, 04:08 PM
#19
[QUOTE]Originally posted by Gr8nbed11
I've been asking around lately and everyone I work with says pretty much the same thing, "Wouldn't the rev limiter kick in and not allow it to get that high of rpms?"
I've been asking around lately and everyone I work with says pretty much the same thing, "Wouldn't the rev limiter kick in and not allow it to get that high of rpms?"