Gear change at ?? RPM / engine cut-off at redline
03-24-2002, 09:47 AM
#16
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[quote]Originally posted by rcwelch:
<strong>This is for the Flying Finn,
I bet you wish that you still had your "75SC", Its a one of a kind being that the rest of the world saw them in 77.
rcwelch
95 993</strong><hr></blockquote>
I still have it, I was fortunate enought to get the first prototype!
Of course she's not SC (to me, she is just so super), she's far from being original so I don't know what to call her really (and haven't paid big attention to it), she's something between -72 to -86 so I sometimes call her that (SC). From now on, I'll call her just 911 (which is what I usually call her anyway) if that's fine with you
. Or actually we could have naming contest, here's a photo of her, what do you guys & gals thin I should call her?
Sorry Zumbera, this has nothing to do with your original question but I guess you alrady have good answer to your question (redline, or close to redline seems to be everybodys answer).
<strong>This is for the Flying Finn,
I bet you wish that you still had your "75SC", Its a one of a kind being that the rest of the world saw them in 77.
rcwelch
95 993</strong><hr></blockquote>
I still have it, I was fortunate enought to get the first prototype!
Of course she's not SC (to me, she is just so super), she's far from being original so I don't know what to call her really (and haven't paid big attention to it), she's something between -72 to -86 so I sometimes call her that (SC). From now on, I'll call her just 911 (which is what I usually call her anyway) if that's fine with you
. Or actually we could have naming contest, here's a photo of her, what do you guys & gals thin I should call her?Sorry Zumbera, this has nothing to do with your original question but I guess you alrady have good answer to your question (redline, or close to redline seems to be everybodys answer).
03-24-2002, 12:23 PM
#17
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[quote]Originally posted by George Helser:
<strong>Zumbera,
In competition, I am sometimes too focused on where I am driving to watch the tach. In that case the 993 rev limiter tells me when it is time to shift!
In summary, shift your 993 at redline for max performance.
</strong><hr></blockquote>
Do all 993s have rev limiters? BTW how does the limiter work?
<strong>Zumbera,
In competition, I am sometimes too focused on where I am driving to watch the tach. In that case the 993 rev limiter tells me when it is time to shift!
In summary, shift your 993 at redline for max performance.
</strong><hr></blockquote>
Do all 993s have rev limiters? BTW how does the limiter work?
03-24-2002, 06:04 PM
#18
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[quote]Originally posted by Zumbera:
<strong>
Do all 993s have rev limiters? BTW how does the limiter work?</strong><hr></blockquote>
Yep they do, I believe it cuts the inition but I'm not sure (at least it weels like that).
<strong>
Do all 993s have rev limiters? BTW how does the limiter work?</strong><hr></blockquote>
Yep they do, I believe it cuts the inition but I'm not sure (at least it weels like that).
03-24-2002, 07:14 PM
#19
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I believe it cuts the ignition (as FF says) to just a couple of cylinders thus dropping power (but not entirely) and allowing the driver to be made aware of the situation, and the loss of power to naturally drop revs back below the cut-out.
Thus if you do not lift off it bounces back above the cut-out as all the cylinders come back on line, then backs off again and carries on the cycle (therefore "bouncing off the rev limiter").
But the great and good of the board will no doubt give a proper explanation.
Cheers... W
Thus if you do not lift off it bounces back above the cut-out as all the cylinders come back on line, then backs off again and carries on the cycle (therefore "bouncing off the rev limiter").
But the great and good of the board will no doubt give a proper explanation.
Cheers... W
03-25-2002, 04:04 AM
#20
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in reply to the guage question you can hace the tac face redone to move the redlint to 12.00.
i have a photo of a cool set just done by hollywood speedometer in calif. they are perfect
i have a photo of a cool set just done by hollywood speedometer in calif. they are perfect
03-25-2002, 04:25 AM
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The handbook says that the engine is prevented from exceeding maximum by means of a cut off in the fuel supply.
That doesnt sound the same as cutting the ignition.
Ah well, Im sure theres already a thread somewhere else about this.
That doesnt sound the same as cutting the ignition.
Ah well, Im sure theres already a thread somewhere else about this.
03-25-2002, 01:02 PM
#22
It seems no one has tackled the “how slow can you go” part of the original question. I’ll take a stab. Here’s the answer: “It depends.” It really, really depends on how much throttle you use. Floor it at 1500 RPM while going up a hill, and you’re gonna lug like crazy. Feather the throttle in a parking lot at 1500, and you’re gonna be fine. The harder you push the throttle, the higher you’d better be in the rev band. Does that help?
There is also some discussion of how the rev limiter works. My belief is that it cuts fuel. The computer simply shuts of the fuel injectors. If you were to cut ignition, and not fuel, you’d be dumping raw the fuel/air mixture into a hot catalytic converter. Can you say “boom?”
There is also some discussion of how the rev limiter works. My belief is that it cuts fuel. The computer simply shuts of the fuel injectors. If you were to cut ignition, and not fuel, you’d be dumping raw the fuel/air mixture into a hot catalytic converter. Can you say “boom?”
03-25-2002, 01:20 PM
#23
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[quote]Originally posted by E. J.:
<strong>Contrary to evident popular belief, I feel that my car stops making usable power at around 6400 or 6500 rpm, so that is where I try and shift - even at the track. Of course I am a little late sometimes though...
Might save a tiny fraction of wear and tear too, you never know. Of course, When I am chasing Greg, I bounce off the limiter (I never catch him though
).
E. J.</strong><hr></blockquote>
Horsepower does drop off at a certain level but the point of running to redline is that your are already up a few hundred rpm at the next gear (thus more power) There are a few times I might not shift at redline but that is so I am not hitting the rev limiter in the middle of a turn. Like turn 12 at Road Atlanta bad place for TTO.
Greg
<strong>Contrary to evident popular belief, I feel that my car stops making usable power at around 6400 or 6500 rpm, so that is where I try and shift - even at the track. Of course I am a little late sometimes though...
Might save a tiny fraction of wear and tear too, you never know. Of course, When I am chasing Greg, I bounce off the limiter (I never catch him though
).E. J.</strong><hr></blockquote>
Horsepower does drop off at a certain level but the point of running to redline is that your are already up a few hundred rpm at the next gear (thus more power) There are a few times I might not shift at redline but that is so I am not hitting the rev limiter in the middle of a turn. Like turn 12 at Road Atlanta bad place for TTO.
Greg
03-25-2002, 02:55 PM
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[quote]Originally posted by Greg Fishman:
<strong>Horsepower does drop off at a certain level but the point of running to redline is that your are already up a few hundred rpm at the next gear (thus more power) There are a few times I might not shift at redline but that is so I am not hitting the rev limiter in the middle of a turn. Like turn 12 at Road Atlanta bad place for TTO.
Greg</strong><hr></blockquote>
Greg,
I would certainly never tell anyone here to shift in the middle of a corner, if you need higher revs after the shift, then run to redline. I know what you are trying to say about the next gear, but since I am not racing (except when behind YOU for some strange reason), I am not as concerned about it as you are. Plus, you have that fancy race gear box that can take the abuse...
E. J.
<strong>Horsepower does drop off at a certain level but the point of running to redline is that your are already up a few hundred rpm at the next gear (thus more power) There are a few times I might not shift at redline but that is so I am not hitting the rev limiter in the middle of a turn. Like turn 12 at Road Atlanta bad place for TTO.
Greg</strong><hr></blockquote>
Greg,
I would certainly never tell anyone here to shift in the middle of a corner, if you need higher revs after the shift, then run to redline. I know what you are trying to say about the next gear, but since I am not racing (except when behind YOU for some strange reason), I am not as concerned about it as you are. Plus, you have that fancy race gear box that can take the abuse...
E. J.
