clutch pedal: metal vs plastic
#1
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clutch pedal: metal vs plastic
I just noticed that the clutch pedal on a 968 is made of plastic, albeit strong plastic. However the clutch pedal on my '84 944 is made of steel.
I recall that the clutch has always felt very stiff or heavy on the 968, and I have spent a lot of time trying to troubleshoot this. I have changed everything but the hydraulics, which I think are ok since the clutch operates fine. Could the plastic pedal potentially be the cause of my heavy clutch? I.e. by flexing and absorbing force?
I recall that the clutch has always felt very stiff or heavy on the 968, and I have spent a lot of time trying to troubleshoot this. I have changed everything but the hydraulics, which I think are ok since the clutch operates fine. Could the plastic pedal potentially be the cause of my heavy clutch? I.e. by flexing and absorbing force?
#2
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I noticed the stiffer clutch between my '84 and my 968 as well. I don't think it's the pedal; it's more likely a higher spring rate on the pressure plate to better cope with the increased power and torque.
For the record, the clutch in my '94 Audi S4 is stiffer than the 968. Just a guess, but I'm thinking it requires even higher clutch clamping force to cope with the increased mass in the quattro system.
For the record, the clutch in my '94 Audi S4 is stiffer than the 968. Just a guess, but I'm thinking it requires even higher clutch clamping force to cope with the increased mass in the quattro system.
#4
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JDS, The stiff clutch hurts my foot long before it hurts my leg muscles. My legs are strong, they're up to the task, but my feet hurt enough on a daily basis!
JPK, a '94 S4? Very cool car. I like that 20vt with EFI. Regarding the clutch, I would agree with you, but I have felt other 968s' clutches, and this one (my '95) is way stiffer. Stiffer even when compared to my '93. I even swapped the entire fw/pp/disk assembly between the two cars, and the stiffness issue stayed with the '95.
Hey, I'm at a loss, so I'm open to ideas!
JPK, a '94 S4? Very cool car. I like that 20vt with EFI. Regarding the clutch, I would agree with you, but I have felt other 968s' clutches, and this one (my '95) is way stiffer. Stiffer even when compared to my '93. I even swapped the entire fw/pp/disk assembly between the two cars, and the stiffness issue stayed with the '95.
Hey, I'm at a loss, so I'm open to ideas!
#5
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Regarding the clutch, I would agree with you, but I have felt other 968s' clutches, and this one (my '95) is way stiffer. Stiffer even when compared to my '93. I even swapped the entire fw/pp/disk assembly between the two cars, and the stiffness issue stayed with the '95.
Hey, I'm at a loss, so I'm open to ideas!
Hey, I'm at a loss, so I'm open to ideas!
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#8
clutch petal
for those who did not experience it,there is a fulcrum pin on the petal
which due to the spring pressure and been made from cheap Mild steel
wears to about 50% of its original diameter ,causing a high petal force
Quite common problem on 18 year old 968
the solution is to replace it with a machined fine finish EN steel pin,for an optimum leverage, as well as the 2 tiny plastic bushes it rotates on.See the PET.
which due to the spring pressure and been made from cheap Mild steel
wears to about 50% of its original diameter ,causing a high petal force
Quite common problem on 18 year old 968
the solution is to replace it with a machined fine finish EN steel pin,for an optimum leverage, as well as the 2 tiny plastic bushes it rotates on.See the PET.
#9
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My cab has a butter smooth pedal. It did not have that with the original setup. I put in a factory 968 clutch setup from sunset porsche and made sure to lubricate the torque tube splines, the clutch splines and used a new needle pin along with needle bearings. I have never had a clutch so smooth in any of my other cars. It is pure butter. Very little effort.
I also adjusted everything, the rods and return springs to factory spec.
If you are not using a factory 968 soecific pressure plate, it will add to a stiffer pedal. Also, lubing the parts helps a lot. I posted some pics of the factory setup. The pressure plates are color coded and should be green in color. Also, a 968 secific pressure plate is only available through the dealer. The same pressure plate sold as oem is actually a 993 pressure plate.
Regards.
Raj
I also adjusted everything, the rods and return springs to factory spec.
If you are not using a factory 968 soecific pressure plate, it will add to a stiffer pedal. Also, lubing the parts helps a lot. I posted some pics of the factory setup. The pressure plates are color coded and should be green in color. Also, a 968 secific pressure plate is only available through the dealer. The same pressure plate sold as oem is actually a 993 pressure plate.
Regards.
Raj
#11
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Taking the spring out would make the pedal so hard, you probably couldn't drive the car.
The setup currently in my '95 968 is all dealership supplied parts, and upon reinstallation into my car, everything was lubed. The pedal is 100% smooth. Just really heavy.
I will look into the fulcrum pin idea, thanks.
So nobody thinks a plastic pedal could possibly cause this?
The setup currently in my '95 968 is all dealership supplied parts, and upon reinstallation into my car, everything was lubed. The pedal is 100% smooth. Just really heavy.
I will look into the fulcrum pin idea, thanks.
So nobody thinks a plastic pedal could possibly cause this?
#13
Bannana Shine
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In other words, it starts at zero force and exerts an increasing force UP on the pedal as you move it towards the floor. So the spring works against your foot, making the pedal heavier, right? Why would removing it make the pedal too hard to use?
To be clear, I'm not telling you to run out to your car and start yanking parts out...I'm just curious what would happen, as it APPEARS that this part was included to add "weight" to the clutch pedal.
#14
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The zero force point is somewhere in the middle of pedal travel, closer to the top actually. Maybe 2-3 inches down from the top. Most of the time, it is helping you push the pedal down. The rest of the time, it is keeping the pedal all the way at the top for your foot.
You know when the slave cylinder fails and the pedal gets "stuck on the floor"? That's because the spring forces it down and keeps it there when there is no back-force from the PP.
You know when the slave cylinder fails and the pedal gets "stuck on the floor"? That's because the spring forces it down and keeps it there when there is no back-force from the PP.