While I have it open, explain launch control
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basically I wire the clutch ground as a switch to enable the launch control.
when the clutch is down and the pedal floored, it will keep the revs at the desired RPM set by retarding the ignition or whatever.
then when released all is normal again? is that it? all i need to do?
then optional (probably wont ever do)
then i can set the flatshift if i want, so I can keep the pedal on the floor above a certain shift point and it will do the same to put the rpms wherever once the clutch is down?
when the clutch is down and the pedal floored, it will keep the revs at the desired RPM set by retarding the ignition or whatever.
then when released all is normal again? is that it? all i need to do?
then optional (probably wont ever do)
then i can set the flatshift if i want, so I can keep the pedal on the floor above a certain shift point and it will do the same to put the rpms wherever once the clutch is down?
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no don't use the clutch pedal because it engages LC EVERY TIME you hit the clutch. Every time. So you get a shudder every time you shift. it's ******* annoying.
use a momentary switch that you can hold while your hand is on the shifter instead. FoundSoul had a good idea--run a master arm switch in series with the momentary switch. that way if you have a passenger, and they hit the momentary, it doesn't engage LC if the arm switch has disabled it. anyway, the concept is with your car in 1st, your hand on the shifter, you're on the gas and clutch and LC is holding you to its rev limiter at say 3.5k rpm and is retarding the **** out of your timing so your egt is nice and hot and spooling the **** out of your turbo. when you go, you take your hand off the momentary button, allowing the engine to rev--and hopefully get traction, and hopefully pull past the ferarri or whatever was next to you.
use a momentary switch that you can hold while your hand is on the shifter instead. FoundSoul had a good idea--run a master arm switch in series with the momentary switch. that way if you have a passenger, and they hit the momentary, it doesn't engage LC if the arm switch has disabled it. anyway, the concept is with your car in 1st, your hand on the shifter, you're on the gas and clutch and LC is holding you to its rev limiter at say 3.5k rpm and is retarding the **** out of your timing so your egt is nice and hot and spooling the **** out of your turbo. when you go, you take your hand off the momentary button, allowing the engine to rev--and hopefully get traction, and hopefully pull past the ferarri or whatever was next to you.
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sounds like a cool feature. Ill get around to doing this one myself as well seeing that I have all the stuff to do the mods, just got a lot of other stuff to button down before I get into icing like this.
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Yep-- haven't played with it yet myself, but it works just the same as launch control... settings are on the same menu. Probably best to use a clutch mounted switch for this.
The stock clutch switch actually works great with launch control... IF you're drag racing, which is also where flat shift would be handy. If you're driving on the street, or road course, etc, the stock clutch switch engages way too far out and it a real pain like Ben mentioned-- as you press the clutch in it enables launch control and limits your RPM, then you shift, and as you get back in the throttle and start to let the clutch out the launch control is still engaged because the switch is at the 'clutch fully disengaged' point. So you have a moment of hesitation while you continue to let the clutch out before you can rev on up. Sucks in such situations.
On a drag strip you'd generally be off the clutch so fast that this wouldn't be an issue, I bet you'd like the stock clutch switch actually.
MORE INFO:
Just did a bit more reading on flat shift in MegaTune (hit F1 from the settings page) and I need to test it but it looks like here's a way to STOP the annoying issue described above when using the stock clutch switch...
The flat shift settings are for use with a clutch switch and allow for different limits when changing gear. To disable, set the arming RPM above you maximum rpm If you press the clutch above the flat shift arming limit then the code uses the flat shift limits, else it uses the launch limits
So for example, set your launch speed at 2500, set flat shift at 6000, and as long as you hit the clutch (and it's switch) above that 2500 launch speed limit then launch control won't engage, instead flat shift will engage and will let you rev out to the flat shift limit (6000 in this example, whatever you set in reality). So this both works for flat shift, and should also get rid of the annoyance in between gears when using the stock clutch switch....
I gotta go try it once I get some sleep-- I've been up all night putting the new shopping cart in place, and it's 7am now.
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The stock clutch switch actually works great with launch control... IF you're drag racing, which is also where flat shift would be handy. If you're driving on the street, or road course, etc, the stock clutch switch engages way too far out and it a real pain like Ben mentioned-- as you press the clutch in it enables launch control and limits your RPM, then you shift, and as you get back in the throttle and start to let the clutch out the launch control is still engaged because the switch is at the 'clutch fully disengaged' point. So you have a moment of hesitation while you continue to let the clutch out before you can rev on up. Sucks in such situations.
On a drag strip you'd generally be off the clutch so fast that this wouldn't be an issue, I bet you'd like the stock clutch switch actually.
MORE INFO:
Just did a bit more reading on flat shift in MegaTune (hit F1 from the settings page) and I need to test it but it looks like here's a way to STOP the annoying issue described above when using the stock clutch switch...
The flat shift settings are for use with a clutch switch and allow for different limits when changing gear. To disable, set the arming RPM above you maximum rpm If you press the clutch above the flat shift arming limit then the code uses the flat shift limits, else it uses the launch limits
So for example, set your launch speed at 2500, set flat shift at 6000, and as long as you hit the clutch (and it's switch) above that 2500 launch speed limit then launch control won't engage, instead flat shift will engage and will let you rev out to the flat shift limit (6000 in this example, whatever you set in reality). So this both works for flat shift, and should also get rid of the annoyance in between gears when using the stock clutch switch....
I gotta go try it once I get some sleep-- I've been up all night putting the new shopping cart in place, and it's 7am now.
MegaSquirt: So many features... so little time
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A few other cars....
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I read something like that about the clutch switch, I was hoping to confirm that.
Maybe I'll wire up a button whever I get to changing the steering wheel...but the concept is sound.
Maybe I'll wire up a button whever I get to changing the steering wheel...but the concept is sound.
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I'm sure that would work. The only problem with a switch is that as you launch you would need to switch it off. A button on the steering wheel or shifter would work better because all you would have to do to turn off the launch control is let your finger off of it. From how I understand it, having launch control on would act exactly the same as a rev limiter and if it is not switched off after the launch, it will not allow the engine to spin up higher than the launch rpm.
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I'm sure that would work. The only problem with a switch is that as you launch you would need to switch it off. A button on the steering wheel or shifter would work better because all you would have to do to turn off the launch control is let your finger off of it. From how I understand it, having launch control on would act exactly the same as a rev limiter and if it is not switched off after the launch, it will not allow the engine to spin up higher than the launch rpm.
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Jerry a.k.a. 'FoundSoul'
DIYAutoTune.com
'91 Miata BEGi S3 GT2560 w/ MSPNP - 14.1psi - 253whp, 232wtq
'95 Miata n/a
A few other cars....
Jerry a.k.a. 'FoundSoul'
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'91 Miata BEGi S3 GT2560 w/ MSPNP - 14.1psi - 253whp, 232wtq
'95 Miata n/a
A few other cars....
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