danes

Guys,

Searched and can't find an answer.

The clutch pedal in my 2007 GT3 RS is very stiff. When I took it in for maintenance the mechanic praised the clutch saying "that's how a real clutch is supposed to feel".

Can someone please explain what is the reason for this stiff clutch, and why it's praised?

Thank you

masmole

It's not that the GT3 has a stiff clutch, it's just that most all other cars have clutches that are way too soft and have absolutely no feel. Too much hydraulic assist on those cars.

I love the GT3's clutch. Gives me a sense of precision and feels easier to operate when driving spiritedly or at the track. It's by design and part of what makes the GT3 feel very connected to its driver. All other cars I've driven with soft clutches feel like junk, including 997 turbos and even my own VW GTI. I guess they're more suited for crawling through rush hour traffic, but not very good when driving the car hard like it's meant to be driven.

If you don't like it now, give it time. Very likely that you'll grow to love it, then anything softer becomes unnatural.

A430v

There's no hydraulic actuator (assist) like the Turbos and regular 911s, hence the stiff clutch. I like it that way - racing pedigree and much more feel. It actually isn't half-bad compared to a Carrera GT.

CRex

You want the easy or the real answer?

Easy answer: you have a man's car. Hence a man's clutch. Case closed

But if that doesn't quite do it for you, here's the long version:

From 993s on (or maybe even earlier) most 911s a few pieces of hydraulics to assist with clutch pressure. Principally, there's (i) an extra reservoir next to the clutch master cylinder (mounted in the front of the firewall next to all the battery & brake gubbins) and (ii) an extra pressure accumulator immediately next to the clutch slave cylinder (mounted on the transmission close to the clutch group).

The reservoir is #8 in the following diagram. Visually, start by looking at #1 which is the master cylinder attached to the clutch pedal. The whole system ends with #21 which is the slave cylinder, attached to clutch release fork in the tranny.



Notice how the whole accumulator & associated attachments are missing from a GT3 (997.1):



Specifically, the reason GT clutches are heavier is because we don't have a pressure accumulator. This thing in real life is a lawnbowl-sized black thingy, the inscription of the side reads 15 BAR which is about 7 times our tire pressure!!



While I haven't opened this thing myself, I speculate the pressure is gaseous not liquid, designed to add clamping force--a very significant one at that--on the clutch beyond what the pressure plate can provide alone.

Whichever version of the answer suits you, this much is clear: you have one of the BEST manual transmission out there. It's heavy but I like it just the way it is. (Glad that doesn't extend to my taste in woman!)

Aerokitted

u only get this level of information... here. thx guys.

a_Y

CRex thanks for the great info!

you just learn something new here everyday =)

andrewgt3

third that.

GeorgeK

2 Remarks:
-Of course there is a reservoir for the clutch hydraulic lines. It can not be a closed circuit, or else it would be of insufficient travel the second the clutch starts to wear. The reservoir is just not on this diagram, but you can see the feed line.

-The pressure accumulator is NOT to increase clamping force. The clutch spring does that.... It is to assist (braking and) clutch actuation. You manage to contradict yourself in 2 contiguous paragraphs.

CRex

Glad I'm open to learning, but can you please elaborate--the accumulator is not something I found in my past two cars nor is it in the parts list. Am I missing something? And the ridiculous pressure inscribed on the side--that can't be liquid can it? I stated my speculation in the original post because these accumulators do fail over time and usually it's because they've developed a gas leak?

Another data point for you: the removal of this accumulator in a TT does make the clutch considerably heavier. What gives? Thanks in advance

GeorgeK

The accumulator usually contains Nitrogen and stores pressure to assist the brakes, and/or the clutch. That is why its failure makes the clutch heavier in the TT, as it does no longer assist the clutch actuation (not clamping).

tcsracing1

in stop and go traffic it is great exercise for the calve muscle

it is one of the hints that the car is competitive in nature ........

deputydog95

This is one of the many reasons the GT3 makes for a horrible daily driver. I got stuck in traffic on the interstate waiting to get by a wreck for 45 mins. I was feeling "the burn" about 5 minutes into it

sws1

So, we see technically how they are different. But what is the reason they chose to not include hydraulic? What advantage does it give? Is it just because "race cars don't do it"?

prg

You think a race car should have a stiff clutch, therefore Porsche gives you one in a GT3.

I've driven a 650+ hp nationwide stock car with a softer clutch pedal than my gen1 gt3rs had. I've driven a lot of a race cars (admittedly mostly lower hp open wheelers), none had a clutch as stiff as a that gt3rs.

Land Jet

OK, I don't have a "man's clutch" in my car, but I can tell you it's a lot easier to modulate both on and off track. You keep the "man's clutch".