Advice for proper launch? 997.1 MT
07-13-2013, 08:09 PM
#1
Pro
Thread Starter
Advice for proper launch? 997.1 MT
What is the correct launch technique for a 997.1 Carrera with 3.6L equipped with sport chrono... Trying to get max acceleration and obviously not destroy my clutch. Have owned the car just over a year but still learning.
e.g. enable sport button, disable PSM or not (will this result in squealing of tires or will it help prevent tire or clutch problems), rev to what RPM, how fast to release clutch, give it more throttle through release or floor it etc..
Advice appreciated!
e.g. enable sport button, disable PSM or not (will this result in squealing of tires or will it help prevent tire or clutch problems), rev to what RPM, how fast to release clutch, give it more throttle through release or floor it etc..
Advice appreciated!
Last edited by zer026T; 07-13-2013 at 09:24 PM.
07-15-2013, 01:49 PM
#2
Instructor
In case no one else chimes in, here is my technique.
I've got an 05 3.6L with sport chrono, so similar car. The only experience I have with timed launching (in order to compare my technique from launch-to-launch) comes from a ProSolo I did a month back. If you're unfamiliar with them, they are an autocross with two identical mirror tracks. Starts are done with a drag-style launch tree. Best reaction time possible is 0.5s (any shorter and you redlight). Good 60 ft times are 2.0s and under. I consistently had 0.6-0.7s reaction times (not that great) but consistent 1.9s 60ft times (pretty good to have marginal reactions yet still put in sub 2second 60fts). I was often facing off against a Caymen S with PDK using launch control. My 60ft times were a little better than the Caymen S with launch. So, I doubt my launches are perfect, but they were good enough to beat most people at 60ft at the ProSolo--even those with launch control.
In general, I try to avoid hard launches. I've got a couple '68 911s with the old 901 transmission. Those would break if you tried to launch off the start. I tend to drive my current car the same way. Course of habit. That means I never ever dump a clutch with a side foot slide. These modern cars may be able take it, but it just seems like I'm playing russian roulette with the transmission.
I believe hard launches will make life harder on a clutch. I could certainly smell my clutch at the ProSolo. I avoid launching the car unless I absolutely need to (e.g. ProSolo). I doubt my technique is the easiest on clutches. But, it'll get you going.
1) PSM OFF. The car will cut the throttle on you as you start to let the clutch out and the wheels begin to spin if you leave PSM on. Nothing quite as depressing as hearing 'Nininininini-bwaaaaaaaa' as the PSM ruins your fun.
2) Sport mode off. I left it off because it shortens the throttle response. I use the throttle to help control spin, so I liked the larger dynamic range with it off.
3) Engine RPMs at maybe 5-6000 rpm. Any higher and I had a hard time controlling wheel spin.
4) Release clutch evenly over maybe half a second. Just slightly slower than I'd let out shifting normally.
5) Control wheel spin with throttle as clutch comes out. Generally at 6000 rpm, I'd get a little wheel spin, but not bad. If the tires started barking at me, I'd back off a little on the throttle. If they weren't spinning and could take a bit more, I'd give it a bit more gas.
Basically, I was trying to control the wheel spin with the release rate of the clutch balanced against the amount of throttle I was giving it. Anyway, that's how I did it.
I'd suggest if you can find a ProSolo nearby to go out and try it. You'll get to practice launching with real times to associate with your various launches, and you'll get to do some autocrossing to boot. It was really a great time.
--Von
I've got an 05 3.6L with sport chrono, so similar car. The only experience I have with timed launching (in order to compare my technique from launch-to-launch) comes from a ProSolo I did a month back. If you're unfamiliar with them, they are an autocross with two identical mirror tracks. Starts are done with a drag-style launch tree. Best reaction time possible is 0.5s (any shorter and you redlight). Good 60 ft times are 2.0s and under. I consistently had 0.6-0.7s reaction times (not that great) but consistent 1.9s 60ft times (pretty good to have marginal reactions yet still put in sub 2second 60fts). I was often facing off against a Caymen S with PDK using launch control. My 60ft times were a little better than the Caymen S with launch. So, I doubt my launches are perfect, but they were good enough to beat most people at 60ft at the ProSolo--even those with launch control.
In general, I try to avoid hard launches. I've got a couple '68 911s with the old 901 transmission. Those would break if you tried to launch off the start. I tend to drive my current car the same way. Course of habit. That means I never ever dump a clutch with a side foot slide. These modern cars may be able take it, but it just seems like I'm playing russian roulette with the transmission.
I believe hard launches will make life harder on a clutch. I could certainly smell my clutch at the ProSolo. I avoid launching the car unless I absolutely need to (e.g. ProSolo). I doubt my technique is the easiest on clutches. But, it'll get you going.
1) PSM OFF. The car will cut the throttle on you as you start to let the clutch out and the wheels begin to spin if you leave PSM on. Nothing quite as depressing as hearing 'Nininininini-bwaaaaaaaa' as the PSM ruins your fun.
2) Sport mode off. I left it off because it shortens the throttle response. I use the throttle to help control spin, so I liked the larger dynamic range with it off.
3) Engine RPMs at maybe 5-6000 rpm. Any higher and I had a hard time controlling wheel spin.
4) Release clutch evenly over maybe half a second. Just slightly slower than I'd let out shifting normally.
5) Control wheel spin with throttle as clutch comes out. Generally at 6000 rpm, I'd get a little wheel spin, but not bad. If the tires started barking at me, I'd back off a little on the throttle. If they weren't spinning and could take a bit more, I'd give it a bit more gas.
Basically, I was trying to control the wheel spin with the release rate of the clutch balanced against the amount of throttle I was giving it. Anyway, that's how I did it.
I'd suggest if you can find a ProSolo nearby to go out and try it. You'll get to practice launching with real times to associate with your various launches, and you'll get to do some autocrossing to boot. It was really a great time.
--Von
07-15-2013, 02:11 PM
#3
Rennlist Member
do not lie to yourself - drag racing starts will destroy your clutch fast and may brake off 1st gear teeth, that requires complete replacement of gearbox. still not a reason not to do that sometimes, as it is fun.
psm off. take revs to 2k or so.
start feeding off clutch until car shows slightest sign of contact in clutch (moves forward), then press clutch just a hair more to brake contact, tap on brakes to stop car
then get revs to 5k-5.5k while maintain clutch in that 'hair off' position. do need to go on revs further, it will abuse clutch much more if you go closer to redline unless you run a competition. at AX I usually launched from 4.5K, just after variocam opens.
on green you press gas all the way down in while dropping clutch, a proper execution on a stick rubber makes car`s rear end 'hop' like a kangaroo and you proper forward.
alternative execution is to do more of a transition in the beginning to avoid 'hopping' but it will burn much more of a clutch material for not that much more speed increase, so, your money, you decide. stock clutches are not designed for such kind of a repetitive abuse, so, it will handle it for a while, but not forever.
typical mistake is to exceed that 'hair off' initial clutch position so clutch plate starts to bounce - it is very bad. try to avoid it.
psm off. take revs to 2k or so.
start feeding off clutch until car shows slightest sign of contact in clutch (moves forward), then press clutch just a hair more to brake contact, tap on brakes to stop car
then get revs to 5k-5.5k while maintain clutch in that 'hair off' position. do need to go on revs further, it will abuse clutch much more if you go closer to redline unless you run a competition. at AX I usually launched from 4.5K, just after variocam opens.
on green you press gas all the way down in while dropping clutch, a proper execution on a stick rubber makes car`s rear end 'hop' like a kangaroo and you proper forward.
alternative execution is to do more of a transition in the beginning to avoid 'hopping' but it will burn much more of a clutch material for not that much more speed increase, so, your money, you decide. stock clutches are not designed for such kind of a repetitive abuse, so, it will handle it for a while, but not forever.
typical mistake is to exceed that 'hair off' initial clutch position so clutch plate starts to bounce - it is very bad. try to avoid it.
07-15-2013, 04:44 PM
#4
The function of the clutch is match the revolutions of the flywheel to the gear selected in the gear box. The bigger the difference in RPM between the two, the more wear and tear you will get with the clutch.
For normal take off I usually rev up to 2,500 RPM and start to release the clutch as I increase RPM's. I never abuse my car but have been told by other Porsche owner friends that for spirited launches 5K RPM and dropping the clutch suddenly works best, all nanny controls off, for maximum launch.
For normal take off I usually rev up to 2,500 RPM and start to release the clutch as I increase RPM's. I never abuse my car but have been told by other Porsche owner friends that for spirited launches 5K RPM and dropping the clutch suddenly works best, all nanny controls off, for maximum launch.
07-16-2013, 09:49 AM
#5
Pro
Thread Starter
Thanks all... I have to remember I'm among some pretty serious race car drivers so I should clarify 
I'm not tracking or on the drag strip, am just looking for advice to get the most out of the car. I plan on a DE event soon, but in the meantime trying to get the right feel for a good solid throw-you-back-in-your-seat kind of launch when you want to see what the car can do. Ultimately help me grow and develop proper launch technique etc... Any further advice appreciated, thank you!
I'm not tracking or on the drag strip, am just looking for advice to get the most out of the car. I plan on a DE event soon, but in the meantime trying to get the right feel for a good solid throw-you-back-in-your-seat kind of launch when you want to see what the car can do. Ultimately help me grow and develop proper launch technique etc... Any further advice appreciated, thank you!
07-16-2013, 09:58 AM
#6
Rennlist Member
at DE you never need to do drag racing start. it is typical for AX runs where you want to puck up max possible speed as fast as you can to save a 1/4 sec or so of your total run time.
07-21-2013, 10:41 AM
#7
Three Wheelin'
+1 on all comments here.
Porsche's are not built for drag strip launches as they have much smaller clutch and other rotating hardware than your Mustang and Corvette's. Porsches are built for going fast around a road race track. Therefore, to get max fun from your Porsche, enroll in DE events. But be aware, it is addictive. For AX, there are probably better cars, such as EVO 8 or newer.....................
Porsche's are not built for drag strip launches as they have much smaller clutch and other rotating hardware than your Mustang and Corvette's. Porsches are built for going fast around a road race track. Therefore, to get max fun from your Porsche, enroll in DE events. But be aware, it is addictive. For AX, there are probably better cars, such as EVO 8 or newer.....................
