Kevlar Timing Belt - Worth it?
11-01-2010, 06:34 PM
#166
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I don't see why horse power and belt strength are being linked. I can see racing vs street use, since the overall operating rpm will be higher and there are lots of fluctuations in rpm with faster shifting. The only other difference would be that engines with higher hp may also have stiffer valve springs.
All else being equal, free revving the engine will put more strain on the belt than any race acceleration condition, regardless of engine hp. Ever wonder why most people who have had the belt break, have "I was leaving a stop sign (or traffic light) when the belt broke" in their posts? Its because we put more strain on the belt leaving from a stop in first gear than we do in a full throttle pull in third gear.
Sure the use of kevlar in this belt is probably overkill. In fact I think its the presence of this, buzz word, material that has fueled this whole thread. Most people are questioning the need of a kevlar belt, when in reality its the rest of the belt material that makes these a good choice. The fact that kevlar is used in the belt's construction is just a secondary feature. But buzz words like kevlar get the sales dept all hot and excited so they push that feature above all else, even if it adds little value to the overall design.
Travis-
Any plans to carry these or a modern non kevlar belt to fit the 968?
All else being equal, free revving the engine will put more strain on the belt than any race acceleration condition, regardless of engine hp. Ever wonder why most people who have had the belt break, have "I was leaving a stop sign (or traffic light) when the belt broke" in their posts? Its because we put more strain on the belt leaving from a stop in first gear than we do in a full throttle pull in third gear.
Sure the use of kevlar in this belt is probably overkill. In fact I think its the presence of this, buzz word, material that has fueled this whole thread. Most people are questioning the need of a kevlar belt, when in reality its the rest of the belt material that makes these a good choice. The fact that kevlar is used in the belt's construction is just a secondary feature. But buzz words like kevlar get the sales dept all hot and excited so they push that feature above all else, even if it adds little value to the overall design.
Travis-
Any plans to carry these or a modern non kevlar belt to fit the 968?
11-01-2010, 06:36 PM
#167
Its the material that last longer and might have a higher shear strenght (on the tooth) 3+ years after the belt is installed.
11-01-2010, 06:40 PM
#168
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Thought I saw some references in this thread to people finding loose teeth on the belts when they change them. In those cases - the fiber core saved them. But this is a pretty muddy thread.
11-01-2010, 06:47 PM
#169
I believe they were referring to the OEM (neoprene) belts. I remember reading that also.
11-01-2010, 07:39 PM
#170
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11-01-2010, 08:03 PM
#171
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11-01-2010, 08:08 PM
#172
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But god DAMN are they stupid.
Ah, who am I kidding? I'd do the same damn thing if I had a Kevlar helmet!
11-01-2010, 10:09 PM
#173
Three Wheelin'
For an example, take the Kevlar core of a timing belt and replace the typical material with, lets say, Automotive Goop (do they still make that product). Would you still want to use it? The ultimate tensile strength will be about the same, but the material that wears against the cogs and holds the teeth into shape, will not be up to the task.
11-01-2010, 10:27 PM
#174
Three Wheelin'
I don't see why horse power and belt strength are being linked. I can see racing vs street use, since the overall operating rpm will be higher and there are lots of fluctuations in rpm with faster shifting. The only other difference would be that engines with higher hp may also have stiffer valve springs.
All else being equal, free revving the engine will put more strain on the belt than any race acceleration condition, regardless of engine hp. Ever wonder why most people who have had the belt break, have "I was leaving a stop sign (or traffic light) when the belt broke" in their posts? Its because we put more strain on the belt leaving from a stop in first gear than we do in a full throttle pull in third gear.
Sure the use of kevlar in this belt is probably overkill. In fact I think its the presence of this, buzz word, material that has fueled this whole thread. Most people are questioning the need of a kevlar belt, when in reality its the rest of the belt material that makes these a good choice. The fact that kevlar is used in the belt's construction is just a secondary feature. But buzz words like kevlar get the sales dept all hot and excited so they push that feature above all else, even if it adds little value to the overall design.
Travis-
Any plans to carry these or a modern non kevlar belt to fit the 968?
All else being equal, free revving the engine will put more strain on the belt than any race acceleration condition, regardless of engine hp. Ever wonder why most people who have had the belt break, have "I was leaving a stop sign (or traffic light) when the belt broke" in their posts? Its because we put more strain on the belt leaving from a stop in first gear than we do in a full throttle pull in third gear.
Sure the use of kevlar in this belt is probably overkill. In fact I think its the presence of this, buzz word, material that has fueled this whole thread. Most people are questioning the need of a kevlar belt, when in reality its the rest of the belt material that makes these a good choice. The fact that kevlar is used in the belt's construction is just a secondary feature. But buzz words like kevlar get the sales dept all hot and excited so they push that feature above all else, even if it adds little value to the overall design.
Travis-
Any plans to carry these or a modern non kevlar belt to fit the 968?
This is why it specifically states in the 944 driver's manual not to let the engine idle excessively.
Light flywheels make the problem worse.
11-01-2010, 10:49 PM
#175
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Gurr.... The kevlar in the belt is great and its true that it is the " last line of defense " but it is by no means the only line of defense.
The teeth have a more robust tooth path coupled with the belt being made out of NHBR polymers to go along with the kevlar bands. These other two parts of the belt allow it to withstand much higher temperatures while being COVERED IN OIL. Lets just take a step back and look at that right there. Even if they didn't have kevlar in them that is a pretty good update right there.
So, the newer cars (100k+ belts) have these other two components of the belt speced out from the factory. This is what makes them 100K belts. The majority of the racing timing belts that Gates already makes are for these cars so they push the "kevlar" part hard. For us, this is just an added bonus to getting an up to date belt for the 944.
Can I just quote this next time the info gets off path again instead of typing it up in a different context every 2 pages because I have a feeling this thread is going to continue on until it reaches the terminal length of the grid girls thread.
The teeth have a more robust tooth path coupled with the belt being made out of NHBR polymers to go along with the kevlar bands. These other two parts of the belt allow it to withstand much higher temperatures while being COVERED IN OIL. Lets just take a step back and look at that right there. Even if they didn't have kevlar in them that is a pretty good update right there.
So, the newer cars (100k+ belts) have these other two components of the belt speced out from the factory. This is what makes them 100K belts. The majority of the racing timing belts that Gates already makes are for these cars so they push the "kevlar" part hard. For us, this is just an added bonus to getting an up to date belt for the 944.
Can I just quote this next time the info gets off path again instead of typing it up in a different context every 2 pages because I have a feeling this thread is going to continue on until it reaches the terminal length of the grid girls thread.
11-02-2010, 06:24 AM
#176
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I do not argue that the belt is not better. I belive it is.
My point is that for stock car its not even close to reasonable.
Second, I find your ebay statement "When it is time to change the timing belt on your 944, this is the ONLY way to go." false.
It is not the only way obviously since 99.9% 944 drivers use regular belts with excellent results. (not to mention 90% belt driven cars on the road that use 10€ timing belts and 0.0001% or less of those belts fail on their own)
My point is that for stock car its not even close to reasonable.
Second, I find your ebay statement "When it is time to change the timing belt on your 944, this is the ONLY way to go." false.
It is not the only way obviously since 99.9% 944 drivers use regular belts with excellent results. (not to mention 90% belt driven cars on the road that use 10€ timing belts and 0.0001% or less of those belts fail on their own)
Last edited by Voith; 11-02-2010 at 07:16 AM.
11-02-2010, 07:13 AM
#177
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11-02-2010, 11:23 AM
#178
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I would complain to Porsche as well for their "There is no substitute" campaign.
(we're digging deep now)
11-02-2010, 11:41 AM
#179
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I do not argue that the belt is not better. I belive it is.
My point is that for stock car its not even close to reasonable.
Second, I find your ebay statement "When it is time to change the timing belt on your 944, this is the ONLY way to go." false.
It is not the only way obviously since 99.9% 944 drivers use regular belts with excellent results. (not to mention 90% belt driven cars on the road that use 10€ timing belts and 0.0001% or less of those belts fail on their own)
My point is that for stock car its not even close to reasonable.
Second, I find your ebay statement "When it is time to change the timing belt on your 944, this is the ONLY way to go." false.
It is not the only way obviously since 99.9% 944 drivers use regular belts with excellent results. (not to mention 90% belt driven cars on the road that use 10€ timing belts and 0.0001% or less of those belts fail on their own)
11-02-2010, 11:50 AM
#180
Race Director
Is the Kevlar Belt available in the rick~roll pattern? If so I will take two.
On a different note....who gives a rats *** how someone sells their products? Or maybe someone is still bitter they got hoodwinked on the Slap-Chop:
On a different note....who gives a rats *** how someone sells their products? Or maybe someone is still bitter they got hoodwinked on the Slap-Chop: