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Does someone know how to unblock the RPM (blocked at 3500RPM) on the 2nd Gen Intrepid's ?
 

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Um...the RPM is not blocked at 3500 RPM, unless you're in Park/Neutral. If you're sitting in park or neutral and wanting to rev the motor up past that, you shouldn't own a vehicle. :biggrin:

If you're talking about "Limp Mode" then that's a different story. Pull your codes if that's the case. :)
 

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i think he is talking about reviing the motor in p or n lol thats a safdety reason if it goes past that u could and might just break the motor mounts
 

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"bUt hOndAs caN dO thAt!!"...
 

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lvdodgeonstock said:
i think he is talking about reviing the motor in p or n lol thats a safdety reason if it goes past that u could and might just break the motor mounts
Yes, it is a safety feature, but not for the reason you mentioned. High revving a motor with no load on it is very bad for internals...and just plain stupid.

alarkyokie said:
"bUt hOndAs caN dO thAt!!"...
LOL! True...but who cares about destroying a Honduh?! :biggrin:
 

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In2Deep said:
...High revving a motor with no load on it is very bad for internals...
When people say that, are they meaning that the motor could overspeed (say go to 7000+ rpm and self-destruct), or are they saying that a motor rev'ing to, say, 6000 rpm with a load on it and briefly staying there will not damage it whereas rev'ing to 6000 rpm and briefly staying there with no load on it will damage it?
 

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Yup.

There is a lot of difference in the way the engine internals behave under loaded vs. no load at any RPM.

Used to be that valves would 'float', I don't know if that's the concern here.
 

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[QUOTE='98-ESer]Yup.

There is a lot of difference in the way the engine internals behave under loaded vs. no load at any RPM.

Used to be that valves would 'float', I don't know if that's the concern here.[/QUOTE]That's why I asked. I disagree that at any given rpm the loading makes a big difference. For example - lets say your traveling on the highway at 5800 rpm. You're saying that as long as it's under load, the engine will be OK, but if you take it out of gear or let up on the gas pedal, the engine might come apart? Please explain. Don't tell me it's because you've removed the downward pressure on the piston so the conn. rod will come apart because if that's so, then what about during the exhaust stroke (no downward pressure then, and also that would mean that if you're at a high rpm but under load (to protect the engine) that if a cylinder misses firing just one time, it comes apart?

Also: Valve float is purely a speed (rpm) phenomenon. It's not like at a given rpm, as long as you have load on the engine, the valves won't float, but at that same rpm with no load, the valves won't float.

Not trying to be argumentative, but we need to discuss this because it doesn't add up.
 

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well who cares about a honda our lug nuts take more torque then that (stock) motor
o and you can do that because its a stick shift
 

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Honda's can not rev to high RPM's in park, or drive for that matter.

My friend owns a 2004 Civic and it cannot rev above 2500 rpms standing still with the brakes applied in drive, and around 3-4k in park/neutral.
 

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Justin said:
My friend owns a 2004 Civic and it cannot rev above 2500 rpms standing still with the brakes applied in drive,

Wont that burn the trans? Its like taking a 5 spd and releasing the clutch till it pulls but not stalls. Its gona burn. tell your friend not to do that. Unless he dosnet care and is going to put a third pedal in it.
 

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Power braking isn't so bad as long as it's not a habit. Once or twice a week at the track is OK. ;)

As for revving in neutral - I can't tell you why it's bad but I've always heard it is. If it's a tall tale then it's a REALLY old one. But it may be as simple as there being a lack of proper cooling to sustain that for very long. After all, if you're at 4k+ RPM's even in 1st the car is moving at over 30 MPH ...
 

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Justin said:
Honda's can not rev to high RPM's in park, or drive for that matter.

My friend owns a 2004 Civic and it cannot rev above 2500 rpms standing still with the brakes applied in drive, and around 3-4k in park/neutral.
park neutral



lol thats a auto i was talking abot a 5 spd
 

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D76G12 said:
...As for revving in neutral - I can't tell you why it's bad but I've always heard it is. If it's a tall tale then it's a REALLY old one...
It's proablay a matter of a concern for over-rev'ing the engine because it has no load (to keep the revs down to a reasonable level). People take that genuine concern - they hear that rev'ing an engine in neutral can cause damage - and misunderstand the reason. They think its because an engine turning a certain rpm, say 6000, without load is more damaging than that same rpm with load. What they are failing to understand is that without load, it's going to a much higher rpm unless limited - that's what I was trying to get across. IOW - It's not the fact that it's not loaded at a given otherwise safe rpm - It's that not having a load will let the rpm go way too high and destroy the engine.

If I was a manufacturer, I might be concerned that, without a park/neutral rpm limiter, a disgruntled customer could try to get even by holding the gas pedal down to hold it at some high but non-catastrophic rpm for several minutes to destroy the engine to create a new-engine warranty claim with no way to really prove that it was an intentionally induced failure. Also, if the gas pedal were floored and there was no limiter, the rpms could go to some catastrophic level - 7000 - 8000 - 9000 rpm with instant destruction (though probably provable).

Probably the manufacturers over the years started seeing either intentional or accidental over-reving in neutral and severe damage, and so are protecting themselves by putting a very safe limit in.
 

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"Also, if the gas pedal were floored and there was no limiter, the rpms could go to some catastrophic level - 7000 - 8000 - 9000 rpm with instant destruction (though probably provable).(peva)
Uh, I disagree... The upper engine limit will be when the engine is using all the fuel and air it can get...Look at hp curves and notice how it drops off as rpm gets out of range.
Mechanical efficiency, or something like that.. Now, add more octane, or alcohol, nitro, ether, Nos, and yeah, something will let go!
 

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so... why would you want to rev over 3k???
 

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alarkyokie said:
"Also, if the gas pedal were floored and there was no limiter, the rpms could go to some catastrophic level - 7000 - 8000 - 9000 rpm with instant destruction (though probably provable).(peva)
Uh, I disagree... The upper engine limit will be when the engine is using all the fuel and air it can get...Look at hp curves and notice how it drops off as rpm gets out of range.
Mechanical efficiency, or something like that.. Now, add more octane, or alcohol, nitro, ether, Nos, and yeah, something will let go!
Yeah - but how much h.p. does it take to spin an unloaded engine to destruction? You might be right - I'm not speaking from experience. But even if it didn't throw a rod or spin a bearing, I bet it would take some life off of it to push the pedal to the metal for a few minutes (without some rev. limiter on it).

Reminds me of a made-for-TV movie that was on some years ago - about some bully in a small town somewhere - drove a late-model Ford pickup truck. He would bully the heck out of everyone in the town, and the law was scared of him too. Finally some citizens got fed up and met him when he pulled up to a store front in his truck. Someone leveled a rifle or shotgun at him and shot him dead thru the windshield. He fell forward and pushed the pedal on the truck to the floor with the engine running in neutral. The final scene faded to black with the crowd just standing there watching and the truck engine whining like crazy but blue smoke just pouring out the exhaust - probably pretty realisitc similar to what you said.
 

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This is to protect the transmission.

The rev limiter on the 2.7 is 6500, 3.2 is 6900
Found out in reverse.

The oil pressure would be higher without load, and the pnuematic load on the valves is much less (virtually non-existant)
The engine mounts would wear from rapid angular acceleration (decel. too) or rapid oscilations, like holding the engine on the ~4k rev limit in P/N, full throttle.
Don't do that.
 

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MikeW said:
This is to protect the transmission.

The rev limiter on the 2.7 is 6500, 3.2 is 6900
Found out in reverse.
Are you sure? My original 2.7 saw more than 6500 on several occasions between 1st-2nd and 2nd-3rd. Of course I also spun a bearing the last time it went that high, but that's besides tha point. :biggrin:
 
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