So today I tried launching my manual transmission C4.

and i notice that you can floor the throttle and the rev limiter stops in 4K REVS and the you just need to feather the clutch

is there any other procedures to do? Or is that the launch control procedure on the manual car

 

991.2?

 

It's not launch control. It's a limitation by Porsche to protect the driveline. That 4K limitation is one of the reasons there is such a large difference in acceleration times between manual and PDK cars. A clutch drop at 6000 rpm would probably close half of that gap.

 

Yep. This is how they showed me to do it at PEC-Atlanta. I felt like I was really abusing the car doing this. Did it back to back 3 or 4 times in a row.

 

I've never launched a car in my life. Is it bad for a manual car to do it? What would be the safest way?

 

have you been in a pdk car? When you do launch control, what is the rpm that the car has the rev limiter on?

i bet is 4K

 

It's 6,500 rpm, at least on the 991.1.

http://www.porscheownersmanuals.com/...ing-on-and-off

 

Launching a car is the most violent thing you can do to a car short of crashing. Do it wrong in a manual and you put your clutch and flywheel at risk.

I'm not saying it will break... there is a video of a magazine doing 50 launches consecutively on a 911 Turbo S... That is extreme violence to the car and drivetrain. Car took it like a champ. No other car with launch control could survive that. GTR goes into limp mode after 2! Done right in a manual and you should be fine but the learning curve could cost a clutch.

 

Any information available from Porsche on how to properly launch a manual 911?

 

No - that's like including how to drift in the manual. Not trying to be a smartass.... Best to check out a PEC and learn on one of their car IMHO.

 

Well, I'd say if you're going to do it... do it. Rev it up to 4k and when you're ready, release the clutch just a hair for a split-second to preload the drivetrain as best as you can. In theory, this will reduce the stress on all sorts of bits... instead of being hit by a diesel locomotive going 100 mph it will be a steam engine only going 90 mph.

But then get your foot all the way off the clutch as fast as you can. The clutch is smoking until you get your foot off the pedal and that's some expensive smoke!

Also, be very ready for a shift into 2nd; it won't take long to get thru 1st gear when you start half-way up the tach.

 

Porsche has engineered PDK Launch Control 3,000 times before you'll have a problem, that's a launch a day , almost everyday for 10 years.

 

I have 2,996 more to go....

 

But the question remains

what is the proper way to launch a manual transmission 991.2? As the revs are limited to 4,000, when on pdk they are on 6,500

i mean, I know how to launch a normal car, but with all this electronic aids, is there a proper procedure?

and like others say, don't worry that much about the strain on your 100k spot car, it is engennired for that, as long as you don't do 20 launches a day

 

I haven't done this on the 911 but I have on other cars. Generally speaking, you should turn off traction control and just drop the clutch at 4,000rpms. The rear tires will spin which takes some of the strain off the driveline and prevents bogging down. I don't think there's any effective way to feather the clutch with your left foot when launching. The traditional method is to drop the clutch.