spec stage 3 launch help
06-03-2016, 10:04 PM
#1
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spec stage 3 launch help I have an M6 04 GTO , could really use some tips on launching with this clutch . im not getting much wheel hop but more spinning .
228r cam
kooks lts w/ catted mids
magnaflow exhaust
aem bruteforce intake
stock driveshaft
drag bags ( at 25psi at track , tires were at 20 ) Yokohama street tires
Some say feather and some say dump at like 3500 . I had a full interior and full trunk my best was a 13.69 making 372whp on a dynojet 248 .
228r cam
kooks lts w/ catted mids
magnaflow exhaust
aem bruteforce intake
stock driveshaft
drag bags ( at 25psi at track , tires were at 20 ) Yokohama street tires
Some say feather and some say dump at like 3500 . I had a full interior and full trunk my best was a 13.69 making 372whp on a dynojet 248 .
06-04-2016, 08:15 AM
#2
The best thing that you can do is get some adjustable rear shocks set on stiff and some drag radials. Launching on street tires at 20# is not going to work unless the track is sticky sticky. It's better to spin than to wheelhop on the driveline. Hop will break stuff pretty quick.
06-04-2016, 02:50 PM
#4
Unfortunately your Spec Stage 3 is rated to around 832 ft/lbs, so a simple quick release of the clutch pedal is going to pull down your 372whp engine fairly quickly. The typical rotating assembly can store an amazing amount of energy. That quick rpm drop on launch is the signature of the rotating assembly's "flywheel effect" in action, which is basically flywheel energy being released from the rotating assembly until either the tires spin or the engine bogs enough to sync up with vehicle speed.
Ideally, the slip time of the clutch needs to be extended out to about .7 seconds or so. That will give your car enough time to accelerate to the point that your engine won't bog when the clutch locks up, and the tires will stay stuck to the track without any wheelhop. Your goal should be to launch the car in such a way that you are basically controlling WOT engine rpm with the clutch pedal. Start by practicing low 3000rpm launches. Slam the throttle WOT while releasing the clutch pedal in a controlled manner with just enough slippage to prevent rpm from dipping below launch rpm. After you've mastered 3000rpm launches, move on up in 500rpm increments. You will get quicker launches from up around your engine's torque peak and beyond, but working your way up from 3000rpm will minimize wear/tear on the drivetrain as you experiment with your technique.
There are other ways to control clutch release time with external hydraulic cylinders or in-line restrictor orifices, but with enough practice you can get similar results from your left foot.
Ideally, the slip time of the clutch needs to be extended out to about .7 seconds or so. That will give your car enough time to accelerate to the point that your engine won't bog when the clutch locks up, and the tires will stay stuck to the track without any wheelhop. Your goal should be to launch the car in such a way that you are basically controlling WOT engine rpm with the clutch pedal. Start by practicing low 3000rpm launches. Slam the throttle WOT while releasing the clutch pedal in a controlled manner with just enough slippage to prevent rpm from dipping below launch rpm. After you've mastered 3000rpm launches, move on up in 500rpm increments. You will get quicker launches from up around your engine's torque peak and beyond, but working your way up from 3000rpm will minimize wear/tear on the drivetrain as you experiment with your technique.
There are other ways to control clutch release time with external hydraulic cylinders or in-line restrictor orifices, but with enough practice you can get similar results from your left foot.
06-05-2016, 12:14 PM
#6
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I had always heard the spec 3 was not designed to be slipped since it was a puck style plate. mostly since everyone running that clutch on a fbody was wearing them down fast and that was the consensus the slipping was prematurely wearing them out.
granted this was back in 05 06 time frame.
granted this was back in 05 06 time frame.
06-05-2016, 03:21 PM
#7
If a clutch didn't slip at all, it would never wear out. The Spec3 may not be designed for long duration slip, but you need it to slip for about .7 seconds if you want a good 60' with street tires or radials.
If it were attached to an engine that was better matched to it's holding capacity, that engine could force the Spec3 to slip longer at full clamp pressure without help from your foot. An alternative is to raise launch rpm to prevent a bog, basically storing more energy in the rotating assy which in turn forces the clutch to slip longer before it can lock up. Either way the clutch is forced to slip longer at full clamp pressure, but it's going to wear less if you instead use your foot to withhold some clamp pressure to achieve the same duration of slip.
The alternative to slipping the clutch is to either allow it to bog the engine or use some inertia energy stored in the rotating assy to knock the tires loose. Tires are easy to change when they wear out, but they are generally more expensive than a clutch disc.
If it were attached to an engine that was better matched to it's holding capacity, that engine could force the Spec3 to slip longer at full clamp pressure without help from your foot. An alternative is to raise launch rpm to prevent a bog, basically storing more energy in the rotating assy which in turn forces the clutch to slip longer before it can lock up. Either way the clutch is forced to slip longer at full clamp pressure, but it's going to wear less if you instead use your foot to withhold some clamp pressure to achieve the same duration of slip.
The alternative to slipping the clutch is to either allow it to bog the engine or use some inertia energy stored in the rotating assy to knock the tires loose. Tires are easy to change when they wear out, but they are generally more expensive than a clutch disc.
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06-11-2016, 01:45 PM
#9
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Hated a Stage 3 and leaving from a dig. Puck styles are on/off switches. The smaller the wheel diameter the larger the sidewall and that absorbs the shock. 15" is ideal but 17" is better than 18"
06-11-2016, 07:22 PM
#10
Too much clutch + not enough engine = on/off switch clutch. Properly match the hit of a Stage 3 to the engine's power, that "shock" from a dig can be completely eliminated without swapping out the clutch. Your car will be quicker, you will break less parts, and you will be able to do it on 17/18 wheels.
06-13-2016, 08:22 AM
#11
06-13-2016, 05:37 PM
#12
Smaller wheels/bigger sidewall is a huge plus when you have more clutch than engine, as something needs to absorb the extra torque that's released when that clutch pulls the engine rpm down.
That's not the case when the clutch is well matched to the engine's torque, as the engine will force that clutch to slip just enough to let the engine maintain rpm when the clutch is dumped. If engine rpm drop is kept to a minimum, the resulting torque spike is also kept to a minimum.
The reason you like your twin over the puck probably has more to do with the twin having less pedal effort, making it easier to modulate clutch slip with your foot. If your clutch were well balanced against your engine's power, there would be no need to slip the clutch with your foot during a WOT launch.
06-14-2016, 10:05 AM
#14
Monster doesn't mind selling you more clutch than you need, as you will be less likely to come back to them with a clutch related problem. People buying increased clutch capacity typically EXPECT more aggressive clutch engagement and generally accept that as part of the "upgrade". While more clutch capacity and less clutch wear will generally make a clutch customer happy, the downside many don't consider is increased transmission/drivetrain abuse.
If a guy wants more clutch capacity without passing more abuse to the rest of the drivetrain, using an external means to delay clutch lockup can make that possible.
06-20-2016, 06:42 PM
#17
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You can do the same launch with your leg as with the screen door shock. Also horsepower has little to do with engagement, it's more of a coefficient of friction as per the friction material on the disc. As Svede was pointing out.
06-20-2016, 06:43 PM
#18
If for some reason you can't get the clutch slip just right, then a flexible sidewall will help. But when you do get the clutch slip right, you can make use of a more efficient tire.
06-20-2016, 06:48 PM
#19