"Proper" way to shift a 3.2 Carrera

[Porsche 911]

A couple of nit-picky questions about shifting:
1) What's the best rpm range to shift up on this G50 transmission? The engine starts to "scream" at 3000 rpm, but from what I hear the real power comes after 4000 rpm

2) After you put the shifter in the next gear, do you ease the clutch out COMPLETELY before adding gas, or do you start adding gas AS you're releasing the clutch? I've been easing the clutch out completely, but notice the rpms spike as soon as it "grabs".

On this note, is it good to apply gas and "rev-match" before releasing the clutch?

3) Double-clutch - any 3.2 drivers who do this?


Thanks in advance..

[cdrik915]

Hi ,

Yes , clutching out totally is needed.

I practice the double clutch , but not very usual with G50 gearbox.

That can help in some situations when gearbox is hard to shift , or used , or cold.

But in normals conditions , not necessary.

Just my 2 cents.

[Porsche 911]

Thanks for the reply.. again, after putting the shifter in the higher gear I need to slowly clutch out completely before applying ANY gas. Shouldn't do both at the same time.

I've been reading up on double clutching, and it seems like something to do while downshifting from 5th to 2nd gear, for example - clutch out with shifter in neutral momentarily before shifting into 2nd gear. It's supposed to match engine and transmission RPM and help "save" the transmission.

Also, is "rev matching" needed in this G50 gearbox when shifting or downshifting?

[twistoffat]

On the up shift you should apply gas slightly and let the cluctch come until you feel it bite.
This is standard for any manual and applies to any car. 1st gear will get you comfortably to 20mph/32kmh and then into second. The way you shift depends on what you are doing. On the street driving conservatively you will probably select 3rd at 30mph 4th at 40 and 5th at 50or 60mph. On the track the gear remains in longer and the rrpm´s go up.
G50 have a syncomesh so many would debate the need to double clutch at all. I personally heel and toe on the downshift under braking.

[Geronimo '74]

Originally Posted by Porsche 911

Thanks for the reply.. again, after putting the shifter in the higher gear I need to slowly clutch out completely before applying ANY gas. Shouldn't do both at the same time.

In real life you will already be pressing the gas pedal a little bit before you have disengaged the clutch completely. There will be a small "overlap"

(like Twistoffat said)

[CMXI]

I always thought that the proper way to shift in any porsche was to start off in first gear rev until just before the rev limit, depress the clutch, engage second gear and then release the clutch pedal while applying full throttle!!

Then apply the same technice for the following gears untill you arrive at the next corner!

[m110]

Under full throttle I generally double clutch on the upshift (freeway on ramp etc)..it just seems smoother to me.

Under partial load, with a G50, it doesn't seem necessary on the upshift for casual driving.

The transmission seems to like being shifted at a certain cadence...there is definitely a G50 sweet spot when engaging the gear that can be felt. The clutch engagement is rather high in the throw so I find myself initiating the shift just as the pedal it coming into the bottom of the arc and therefore the the transmission has already declutched fully. Throttle response is not terrific so I do have the gas coming down before totally clutched, but depends on how fast I am shifting.

Out of habit I double clutch on nearly every downshift, even when shifting into first as a coast to a stop.

I'd be interested to know who double clutches on the upshift regularly.

[dshepp806]

I'm VERY gentle on my G50,..not too often redlining 1st gear. I take my time getting to the subsequent gear,..sometimes DC'g.....just making sure I don't "feel" anything within the shift,..that way I know the gears are happy.......never speed shift (?)

As an aside (and I don't know what thread I picked this from,..but was from a knowledgable P-guy......when dead cold (startup)...I always position 3rd gear BEFORE I position #1 gear.......the guy referred to it as "staging" the gears.... (WTF?)....makes for an easy entry into 1st.

I baby my G50....yet rev matching is a must!!!!!!!!


Doyle

[aston@ultrasw.c]

double clutch on the upshift is nonsense

double clutch on the downshift is optional

Rev match aka heel and toe on the downshift is essential

To optimise shifting, adjust the clutch stop so that the pedal only travels far enough to separate the clutch.

[etcmss]

so what is screaming? mine just came out of winter hibernation and it doesn't scream at 3000. 4500 + maybe...
this winter i replaced the chip with S. Wong (previous was a P ??? model). and it is so much more calm and consistent. the last 2 days i drove it to work and every gear smooth shift 4000-4500 and normal slow or medium acceleration.
it gets going well above 3000.... go enjoy it.
stock chip? the S wong one is well worth it and i do hear differences with it. it doesn't sound like its straining.

[teenerted1]

somethings wrong if it is screaming at 3k...that is where most people dont drive below.

[nesslar]

"...double clutch on the upshift is nonsense..." Have to admit, I wondered about that "on the upshift" stuff. And at 50 I wouldn't even think about 5th.....not even 4th normally, as the car gets too quiet... Oh, wait, I have a 915....I do have a 3.2, however, but it never screams; does make some serious kind of growl/happy noise, though....

[tazzieman]

Change up when the engine starts to sound a little "angry". 3500-4000 minimum.

[nesslar]

Very good. I think "angry" describes it well; reminds me of a few neighbors, lol, even though I wasn't even speeding; stock exhaust and all, but stuff happens.............

[TimT]

double clutch on the upshift is nonsense

double clutch on the downshift is optional

Rev match aka heel and toe on the downshift is essential

To optimise shifting, adjust the clutch stop so that the pedal only travels far enough to separate the clutch.

+1

Shifting

Learn to shift like this

http://www.rudtnersracing.com/Videos/WatkinsGlen05.wmv

No double clutch on upshift, nor on downshift.. Just rev matching...

BTW it is a G50 in the 935 we built


at one point in the video the cars pass through a ripple in the space/time continuum. and there is a missed shift also..

[m110]

[QUOTE=TimT;5907887]+
No double clutch on upshift, nor on downshift.. Just rev matching...


QUOTE]

What is the technique for rev matching while downshifting, without double clutching? Are you increasing and matching the engine rpm without speeding up the transmission input shaft? Doesn't that leave clutch friction to speed up the transmission?

[Nine17]

I prefer to lurk on threads like this, but shifting is one of my favorite pastimes so I guess that I'll weigh-in...

1) The 3.2 really starts kicking-in at about 5000 rpm. My car has a Steve Wong chip and seems to want to be revved to about 7000. However, first gear on the G50 is kind of a stump-puller and I tend to get out of it early to get on with things. Of course, around town you probably ought to stay out of that part of the rev range, CMXI's excellent advice notwithstanding...

2) There is a matter of semantics when dealing with terms like "in" and "out" with the clutch. When the pedal is "in" the clutch is disengaged, or "out." When the pedal is "out" the clutch is engaged, or "in."

3) The better you match revs, the less wear on your clutch, and the less you will upset the balance of the car -- the "friction circle" as they call it at Skip Barber. When upshifting you should be feeding in a little throttle as you engage the clutch so that the speed of the engine and the transmission are compatible for a smooth engagement. If you wait for the clutch pedal to fully release, you are using clutch slip (and wear) to match the engine and transmission revs and will experience driveline "snatch" as you describe.

4) The same is true about rev-matching on downshifts, only even more critical to traction and overall balance. This is where proper heel-and-toe technique can make a huge difference when braking and downshifting. I've been spoiled by driving late-model BMW's for nearly 20 years, which have perfect brake/throttle alignment for this. I wound up spending a silly amount of money to install a Smart Racing Products foot-rest and a Rennline adjustable throttle pedal to achieve heel-and-toe nirvana in my Carrera. Three-time Thunderhill 25 winner Rich Walton of Jerry Woods Enterprises has told me that the late 3.2's have a plastic throttle pedal that was apparently designed for the 60 Minutes "Unintended Acceleration" scare and it's just too long a reach to properly heel-and-toe these cars.

5) I always, always, always double-clutch when downshifting. Your transmission and clutch will thank you. Even with the strong syncros of the Getrag gearbox, engagement will always be smoother -- even downshifting from second-to-first on the fly is a piece of cake. It's not necessary to double-clutch when upshifting, but a slight pause crossing neutral will result in better gear engagement.

All of these techniques can become second-nature and will take less than a second to execute. Thank you for your interest in one of the great pleasures of driving!

[Quicksilver]

Shifting is one of the places where you will find really good drivers abusing there equipment, especially when they are operating under the excitement of "going fast".

Tips to improve the shifting portion of your driving:

• Do not grab the shifter in your fist like a baseball bat. Shifting correctly doesn't take much force and if you grab the thing you will at some point end up forcing it. Instead use your fingers. Use 2 or 3 fingers to move the shifter. That will generate plenty of force but limit the possibility of using brute force. An added bonus is if you are moving really fast the flexibility of your fingers acts as a shock absorber to allow more time for that moment when the syncros are doing their work. Feel that point of contact. All your cars will thank you (Unless you are aiming your couch... I mean driving an automatic. )
• Learn to heel-toe to the point where you don't think about it. If you have to think about it you will never be good at it. If you have it down to an automatic action you will always be heel-toeing every stick car you drive. The best way to learn this is to get a crappy car that won't idle unless you keep your foot on the gas. If you live in the north get an old car/truck and disconnect the choke. By the end of winter you will have learned a skill that you couldn't forget if you wanted to.
• Learn how to rev match during your shifts. Listen to the engine note. If you hum the tone of the engine you know how much the engine note will change during a shift. Just make that happen and let the speed of engagement be timed to the engine note. You have to know how to heel-toe to rev match the downshifts because the engine speed goes up during those shifts. If you feel any touch of acceleration or deceleration at the moment of engagement then you still have room for improvement. (You will never stop improving)
• Double clutching is a really good skill to have (even if it is unnecessary on a modern synchronized transmission) but is really hard to learn on any car with a synchronized transmission. You might think you have double clutching nailed but you will never really know unless you drive a car with no syncros. The solution to learning this is familiar: Get a really crappy car that has the syncro toasted in the transmission. I never knew how bad (or good) my double clutching was until the "rebuilt" trans that I put in my truck swallowed the syncros (just past then 90 day warranty). Having something that will violently grind every time you do it slightly wrong will turn it into a reflex in no time.

[Porsche 911]

So what I've taken so far:
1) The consensus seems to be to add gas AS you're easing out (engaging) the clutch and NOT wait until it is fully engaged before adding gas

2) Rev-matching on upshifts - when you add gas AS you're easing out the clutch, you're kind of doing this. Get the rpms to around 2000 before letting the clutch "grab"

3) Rev-matching on downshifts - similar.. basically the same technique? Apply gas AS you're easing out the clutch but get the RPMs even higher than 2000 before letting the clutch "grab"

Heel-to-toe on my 3.2 does seem harder given the reach, especially since I put sandpaper on all 3 pedals to help with the grip. I won't be doing this anytime soon:

YouTube - Race Car Driver & His Footwork

4) Always double-clutch when downshifting


..feel free to let me know if I'm missing something

[MdR]

Originally Posted by Quicksilver

The best way to learn this is to get a crappy car that won't idle unless you keep your foot on the gas

I learnt to drive in a knackered Beetle. That'll do it.

I wonder if folk maybe over thinking the gear change, especially for a street car.