How the hell do you use launch control?
#1
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How the hell do you use launch control?
I just got LC hooked up and enabled. Set to the default 2500 RPM I just waste the tires unless I'm really feathering the clutch. I'm finding it much harder to launch consistently. Is there some sort of trick to this?
#4
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Not sure. I wasn't looking at the screen. The functionality of the hardware is not in question, though. It is working. Limiter kicks in at 2500.
I'm just not sure how useful the feature is, considering I have traction problems off the line even without LC.
I'm just not sure how useful the feature is, considering I have traction problems off the line even without LC.
#7
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I guess what I'm asking is: Is burning the hell out of the clutch really the way LC is used? Otherwise I really don't see the usefulness of the feature. Maybe lowering the setpoint to, like 1500rpm?
#8
Not for drag racing.
Untill now meaning hooking up launch control? Or now as in turbo charging your car?
Try throwing some ET radials on and report back on the usefulness of LC.
Keep in mind LC is not traction control. It does one specific thing, which is give you a second rev limiter when you've got the clutch in. It's not going to stop wheel spin if you dump the clutch at 2500RPM where you'd have wheelspin without it at 2500RPM.
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There are basically three ways to launch a car that I'm aware of.
1: Let out the clutch nice-n-easy with minimal (or no) throttle application. Easy on tires, easy on the clutch, slow.
2: Floor the throttle, release the clutch, resulting in wheelspin. Hard on tires, hard on the clutch, slow.
3: Launch control: Floor the throttle and have the computer hold it at a fixed RPM while you release the clutch, such that wheelspin is reduced or eliminated. Hard on the clutch, easy on the tires, fast.
If you're still getting wheelspin with RT-615s (and they're not old and hard) then congratulations- you have a manly engine.
Start by decreasing the ignition timing in launch mode even further. I believe the default is -10 (which is 10° BTDC) so try moving it back to -5, or even 0. If that does not cure it, try reducing the limiter RPM until wheelspin is eliminated. You'll come out at a lower RPM, but the turbo should still be fully spun up.
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Fastest way off the line when I had LC hooked up was to set the limiter at around 3500, and then engage the clutch enough to get off the line, but not enough to let the LC turn off. Wait a split second while you let the car catch up with the tires at 3500rpm, then step off the clutch, turn off the rev limiter, and let it rev 1st gear out completely.
If you just feather quickly, then step off, it's a great way to lay long stripes to impress your friends. Not fast, though.
If you just feather quickly, then step off, it's a great way to lay long stripes to impress your friends. Not fast, though.
#14
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Fastest way off the line when I had LC hooked up was to set the limiter at around 3500, and then engage the clutch enough to get off the line, but not enough to let the LC turn off. Wait a split second while you let the car catch up with the tires at 3500rpm, then step off the clutch, turn off the rev limiter, and let it rev 1st gear out completely.
#15
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Are you using spark cut only or spark and fuel? Spark cut by itself is too aggressive for me regardless of what tires I'm running - it builds too much boost. I switched to spark and fuel cut, and that was the sweet spot for me (6psi).
#16
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Track cars dont need flat shifting.
Its more of a "fun, hey look what my car can do" kinda thing to me. I do not ever plan to seriously drag race the car but its fun to crack it open every now and then.
I used my flat shift a few times @ laguna. It doesn't make me any faster. Only fun.
#18
I might have something to contribute to this thread if I'd ever sorted out why my launch control doesn't work.
You should have seen some of the other workers ducking for cover and questioning the health of the offending car when you'd go by on the front straight and blow shotgun shells out of the exhaust!
You should have seen some of the other workers ducking for cover and questioning the health of the offending car when you'd go by on the front straight and blow shotgun shells out of the exhaust!
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