New chip, clutch and launching issues
10-15-2003, 01:58 AM
#1
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New chip, clutch and launching issues
Trying out a new line of chips (not sure of name, but something like No More Bad Days Chips . . .) as the price was cheap and I was curious as to whether I really had Ruf chip as I was told.
I usually run about 5.4s on the Gtech, but I have big 18 inch wheels and a decent amount of wieght in stereo gear.
The chip I used today switches between normal and power mode on a three position switch. I was switching between the two outside positions and running between 5.8 and 6.0 and one 6.2 (well over 10 runs). I did not have instructions and it turns out power mode was middle, not left or right. My old chip is definitely hotter than what is factory mode on the new chip.
I reset and switched to middle or power mode. To keep from just spinning the wheels, I kind of feathered the clutch so to speak and it did not fully engage. I launched hard, but the clutch never really enagaged, was slipping and staying about 2k over what should have been until I feathered the gas at about 5k. I did the same thing in 2nd.
No burning clutch smell and I have done this before without burning clutch smell.
Question is, is my clutch about toast even though I can still dump it hard and light up the rears wheels in first and second. So it bad clutch or just bad driving.
I usually run about 5.4s on the Gtech, but I have big 18 inch wheels and a decent amount of wieght in stereo gear.
The chip I used today switches between normal and power mode on a three position switch. I was switching between the two outside positions and running between 5.8 and 6.0 and one 6.2 (well over 10 runs). I did not have instructions and it turns out power mode was middle, not left or right. My old chip is definitely hotter than what is factory mode on the new chip.
I reset and switched to middle or power mode. To keep from just spinning the wheels, I kind of feathered the clutch so to speak and it did not fully engage. I launched hard, but the clutch never really enagaged, was slipping and staying about 2k over what should have been until I feathered the gas at about 5k. I did the same thing in 2nd.
No burning clutch smell and I have done this before without burning clutch smell.
Question is, is my clutch about toast even though I can still dump it hard and light up the rears wheels in first and second. So it bad clutch or just bad driving.
10-15-2003, 07:18 PM
#2
Burning Brakes
If you can still dump the clutch and light up the rears, then your clutch is ok. Sounds like you just gave it too much when it slipped before.
No burning smell though? don't understand that.
I once popped the clutch too high and it slipped. The car still smelled of clutch the morning after ! it was nasty.
No burning smell though? don't understand that.
I once popped the clutch too high and it slipped. The car still smelled of clutch the morning after ! it was nasty.
10-15-2003, 11:05 PM
#3
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I think my clutch is a little screwed up/out of adjustment. Tough to say as it is so different from the clutch feel on my TT. I am sending car back to shop for a new clutch and a full service/valve adjustment. No fun after just dumping $ 2,400 + about two weeks ago, but I cannot stand to have a car not feeling right. Runs strong now, but I think I am not at 100 percent.
10-16-2003, 10:33 AM
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Doug,
Just so we're clear, there is no engagement during the first 2-3 inches of clutch travel. Many new p-car drivers learn this the first time they try to drive these goofy cars. As with a normal car, they apply some gentle throttle as they ease out the clutch. Of course, since there's no engagement, the revs keep climbing so they ease off the gas just as the clutch finally grabs hold. Result: one beautifully executed stall.
When trying for a quick launch, I give the pedal a few pumps, try to hold the revs at around 2,000 rpm, then bring it back quickly--but not a complete dump--as I feed in the gas. At autocross the other day, I actually got all four wheels to spin as I shot out of the first gate.
So is what you're experiencing different from the first few inches of dead space I mentioned?
Just so we're clear, there is no engagement during the first 2-3 inches of clutch travel. Many new p-car drivers learn this the first time they try to drive these goofy cars. As with a normal car, they apply some gentle throttle as they ease out the clutch. Of course, since there's no engagement, the revs keep climbing so they ease off the gas just as the clutch finally grabs hold. Result: one beautifully executed stall.
When trying for a quick launch, I give the pedal a few pumps, try to hold the revs at around 2,000 rpm, then bring it back quickly--but not a complete dump--as I feed in the gas. At autocross the other day, I actually got all four wheels to spin as I shot out of the first gate.
So is what you're experiencing different from the first few inches of dead space I mentioned?
10-16-2003, 02:23 PM
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There is no difference in the operation of a RUF clutch for the DMF fitted 964 and any other clutch plate apart from how the clutch lining is attached to the plate.
Only the 1989 C4 is fitted with a rubber centred clutch plate.
Other 964s fitted with SMFs use spring centred clutch plates exclusing of course the race cars like the RS NGT which uses a specially shaped lightweight racing clutch plate.
Ciao,
Adrian
964C4
Only the 1989 C4 is fitted with a rubber centred clutch plate.
Other 964s fitted with SMFs use spring centred clutch plates exclusing of course the race cars like the RS NGT which uses a specially shaped lightweight racing clutch plate.
Ciao,
Adrian
964C4
10-16-2003, 06:41 PM
#7
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That is interesting though. My clutch is very heavy and I asked my shop which basically specializes in Porsche track cars and has built several 964 RS track cars about my clutch. He said it felt different than the normal 964 clutch, but that everything seemed fine and I had plnty of clutch left. This was two seeks ago.
It maybe a Ruf clutch. It does fell like the through out bearing or something is out of adjustment on it. I was told something to this effect, but my wrench said it won't hurt anything and if you would have to dissamble it to re adjust or do what ever he was talking about.
I drove the car the car today it is driving like a bat out of hell. I was hitting 5.3 0 - 60s and third gear from about 60 to 105 is incredibly fast. Feels almost like (not quiet though) my TT for that brief period between about 80 and red line in third gear.
I think as far as electronics and parts I am in great shape. I have a feeling I need a valve adjustment or I am loosing just a little bit of hp because of one or two old plugs or maybe a leak around one of the valves. Just a weird inconsistent feeling. I may be totally wrong, but I bet I will see some 5.2s after a thorough service and if I pull my sub out (50 pounds).
I have to say that I am very pleased with the 964 and like it much better than my old 88 3.2 overall.
It maybe a Ruf clutch. It does fell like the through out bearing or something is out of adjustment on it. I was told something to this effect, but my wrench said it won't hurt anything and if you would have to dissamble it to re adjust or do what ever he was talking about.
I drove the car the car today it is driving like a bat out of hell. I was hitting 5.3 0 - 60s and third gear from about 60 to 105 is incredibly fast. Feels almost like (not quiet though) my TT for that brief period between about 80 and red line in third gear.
I think as far as electronics and parts I am in great shape. I have a feeling I need a valve adjustment or I am loosing just a little bit of hp because of one or two old plugs or maybe a leak around one of the valves. Just a weird inconsistent feeling. I may be totally wrong, but I bet I will see some 5.2s after a thorough service and if I pull my sub out (50 pounds).
I have to say that I am very pleased with the 964 and like it much better than my old 88 3.2 overall.
Last edited by Doug H; 10-16-2003 at 10:02 PM.
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10-17-2003, 05:00 AM
#8
Originally posted by Doug H
I was hitting 5.3 0 - 60s and third gear from about 60 to 105 is incredibly fast.
I was hitting 5.3 0 - 60s and third gear from about 60 to 105 is incredibly fast.
BTW, your signature states that you have a 'RUF cab'. Why - can you give some more details?
10-17-2003, 08:42 AM
#12
