Timing belt reinstall - Another PK tensioner over extended?
06-02-2016 | 12:48 PM
#151
Three Wheelin'
Joined: Feb 2002
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The posts you make on this stating that it has to work on every engine without modification or Ken should redesign and fix the bracket, or issue a recall is the exact reason many people don't build things or sell kits for the 928.
For the vast majority of cars his system works as intended. If it doesn't work in your application, or you don't want to modify the bolt holes, then either modify the system to work in a way you're happy with, or simply put don't use it.
But for you and others to come on here and bash it and say it's junk or not ready to be sold to the public because it isn't tested enough is frankly infuriating to those of us who do build things for these cars. Attitudes like this are the very reason I don't tell most people past my own personal customers/friends about some of the stuff I make and leave them as 1 off pieces.
Instead why not take a step back and realize that there is no way for ken to build a system which will cover all 928s with the variations between them. Understand that you can modify it to work for you in a way that you're happy with, or just simply put, not use the product.
If you're working on a car that already has it and you don't like it, send the customer elsewhere or tell them to revert to stock. If the customer wants you to continue to do the work, they will take your advice.
For the vast majority of cars his system works as intended. If it doesn't work in your application, or you don't want to modify the bolt holes, then either modify the system to work in a way you're happy with, or simply put don't use it.
But for you and others to come on here and bash it and say it's junk or not ready to be sold to the public because it isn't tested enough is frankly infuriating to those of us who do build things for these cars. Attitudes like this are the very reason I don't tell most people past my own personal customers/friends about some of the stuff I make and leave them as 1 off pieces.
Instead why not take a step back and realize that there is no way for ken to build a system which will cover all 928s with the variations between them. Understand that you can modify it to work for you in a way that you're happy with, or just simply put, not use the product.
If you're working on a car that already has it and you don't like it, send the customer elsewhere or tell them to revert to stock. If the customer wants you to continue to do the work, they will take your advice.
It is so disappointing to continually see the dog piling all over the same opinions. It really ruins the fun of doing any sort of engineering and invention surrounding these cars.
For those who just can't stop themselves... carry on.
06-02-2016 | 12:52 PM
#152
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The engineering minds already involved are far better than mine, however I would like to be involved and can add logistics, supply parts, alternative parts and some financial help.
Sounds like we are on the right track - collectively we can overcome any issue.
Sounds like we are on the right track - collectively we can overcome any issue.
__________________
Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
George Layton March 2014
928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission?
George Layton March 2014928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
06-02-2016 | 12:56 PM
#153
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The design parameters are between 2-7mm piston extension.
The posts you make on this stating that it has to work on every engine without modification or Ken should redesign and fix the bracket, or issue a recall is the exact reason many people don't build things or sell kits for the 928.
For the vast majority of cars his system works as intended. If it doesn't work in your application, or you don't want to modify the bolt holes, then either modify the system to work in a way you're happy with, or simply put don't use it.
But for you and others to come on here and bash it and say it's junk or not ready to be sold to the public because it isn't tested enough is frankly infuriating to those of us who do build things for these cars. Attitudes like this are the very reason I don't tell most people past my own personal customers/friends about some of the stuff I make and leave them as 1 off pieces.
Instead why not take a step back and realize that there is no way for ken to build a system which will cover all 928s with the variations between them. Understand that you can modify it to work for you in a way that you're happy with, or just simply put, not use the product.
If you're working on a car that already has it and you don't like it, send the customer elsewhere or tell them to revert to stock. If the customer wants you to continue to do the work, they will take your advice.
The posts you make on this stating that it has to work on every engine without modification or Ken should redesign and fix the bracket, or issue a recall is the exact reason many people don't build things or sell kits for the 928.
For the vast majority of cars his system works as intended. If it doesn't work in your application, or you don't want to modify the bolt holes, then either modify the system to work in a way you're happy with, or simply put don't use it.
But for you and others to come on here and bash it and say it's junk or not ready to be sold to the public because it isn't tested enough is frankly infuriating to those of us who do build things for these cars. Attitudes like this are the very reason I don't tell most people past my own personal customers/friends about some of the stuff I make and leave them as 1 off pieces.
Instead why not take a step back and realize that there is no way for ken to build a system which will cover all 928s with the variations between them. Understand that you can modify it to work for you in a way that you're happy with, or just simply put, not use the product.
If you're working on a car that already has it and you don't like it, send the customer elsewhere or tell them to revert to stock. If the customer wants you to continue to do the work, they will take your advice.
06-02-2016 | 02:23 PM
#154
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Joined: Feb 2005
Posts: 15,230
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From: Anaheim
One comment about making the Portensioner fit "universally".
All of these engines are going to get rebuilt (or have a valve job) and most are going to get the heads "shaved". Most people appreciate the slight increase in compression, so it is infrequent (never) that people buy the optional thicker head gaskets. Most likely, this common work is going to put the current Portensioner "out of range".
I think it would probably be good, if people could use their same tensioner/damper system after the engine got rebuilt or had a valve job, instead of having to figure out what they did with their stock pieces and put them back on.
Simple slotted adjustability with a secure stop to keep the hydraulic tensioner from slipping away would allow people to re-adjust the tensioner position back to the "sweet spot".
All of these engines are going to get rebuilt (or have a valve job) and most are going to get the heads "shaved". Most people appreciate the slight increase in compression, so it is infrequent (never) that people buy the optional thicker head gaskets. Most likely, this common work is going to put the current Portensioner "out of range".
I think it would probably be good, if people could use their same tensioner/damper system after the engine got rebuilt or had a valve job, instead of having to figure out what they did with their stock pieces and put them back on.
Simple slotted adjustability with a secure stop to keep the hydraulic tensioner from slipping away would allow people to re-adjust the tensioner position back to the "sweet spot".
06-02-2016 | 02:33 PM
#155
Captain Obvious
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From: Cambridge, Ontario, Canada
The design parameters are between 2-7mm piston extension.
The posts you make on this stating that it has to work on every engine without modification or Ken should redesign and fix the bracket, or issue a recall is the exact reason many people don't build things or sell kits for the 928.
For the vast majority of cars his system works as intended. If it doesn't work in your application, or you don't want to modify the bolt holes, then either modify the system to work in a way you're happy with, or simply put don't use it.
But for you and others to come on here and bash it and say it's junk or not ready to be sold to the public because it isn't tested enough is frankly infuriating to those of us who do build things for these cars. Attitudes like this are the very reason I don't tell most people past my own personal customers/friends about some of the stuff I make and leave them as 1 off pieces.
Instead why not take a step back and realize that there is no way for ken to build a system which will cover all 928s with the variations between them. Understand that you can modify it to work for you in a way that you're happy with, or just simply put, not use the product.
If you're working on a car that already has it and you don't like it, send the customer elsewhere or tell them to revert to stock. If the customer wants you to continue to do the work, they will take your advice.
The posts you make on this stating that it has to work on every engine without modification or Ken should redesign and fix the bracket, or issue a recall is the exact reason many people don't build things or sell kits for the 928.
For the vast majority of cars his system works as intended. If it doesn't work in your application, or you don't want to modify the bolt holes, then either modify the system to work in a way you're happy with, or simply put don't use it.
But for you and others to come on here and bash it and say it's junk or not ready to be sold to the public because it isn't tested enough is frankly infuriating to those of us who do build things for these cars. Attitudes like this are the very reason I don't tell most people past my own personal customers/friends about some of the stuff I make and leave them as 1 off pieces.
Instead why not take a step back and realize that there is no way for ken to build a system which will cover all 928s with the variations between them. Understand that you can modify it to work for you in a way that you're happy with, or just simply put, not use the product.
If you're working on a car that already has it and you don't like it, send the customer elsewhere or tell them to revert to stock. If the customer wants you to continue to do the work, they will take your advice.
You know that the car I'm working on has one. I don't like it but since it's already there and the scope of work does not include the timing belt (other than re stringing it after valve springs are change), I'm not going to tell him to fork out more money on this car. I checked the tensioner extension as it looks good. On top of that, there is nowhere else to send him (not that I want to). You know the background and the nightmare the owner had to go though with the car already, all he needs is another hack job. Speaking of hack jobs, the steering rack was sent for a rebuild to a shop that does nothing but rack rebuilds and the diagnosis was that there were part/s missing and part/s installed in the wrong order that cause the rack to blow the seal.
06-02-2016 | 02:34 PM
#156
Three Wheelin'
Joined: Mar 2011
Posts: 1,805
Likes: 500
From: Columbus, OH
Sorry for the misunderstanding but I realized that others reading may not be as knowledgeable as you. I absolutely did not mean to diminish your work.
Different amounts of valve spring tension at different crank angles and the temperature of the components will change the reading as you indicated.
I do not know why the reading is higher on your engine.
In designing the final bracket I experimented with many forms of the bracket and different methods of making it adjustable, including slotting the upper holes but it did not help. Modifying the tensioner/damper (to a size that already exists on the T/D) was the simplest and best option that works without making a whole range of brackets.
Different amounts of valve spring tension at different crank angles and the temperature of the components will change the reading as you indicated.
I do not know why the reading is higher on your engine.
In designing the final bracket I experimented with many forms of the bracket and different methods of making it adjustable, including slotting the upper holes but it did not help. Modifying the tensioner/damper (to a size that already exists on the T/D) was the simplest and best option that works without making a whole range of brackets.
06-02-2016 | 03:19 PM
#157
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From: Park Ridge, IL (near Chicago)
It's been a while since I've had the PK tensioner in my hands but due to the leverage, I think 2-7mms at the tensioner translates into more movement than that at the pulley.
Dave
Dave
06-02-2016 | 04:50 PM
#158
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From: ɹəpun uʍop 'ʎəupʎs
No, there are multiple factory tensioners used on 928's.. different numbers of washers (and hence different amounts of un-tensioning), different tensioner bolts, and different physical housings, across the various model years.
06-02-2016 | 04:51 PM
#159
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There are many different variations of the stock tensioner. To think there is a one size fits all from the factory on our cars is delusional.
06-02-2016 | 04:53 PM
#160
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From: Double Oak, TX
Ken, Why did you go to the BLACK bracket? I just installed a new, never used, GOLD bracket PKTensioner in my 84 Euro (it came with the car). Should I have concerns about the reliability of this tensioner? Thanks, Joel
There was a recall about two years ago with update kits for those that expressed interest.
06-02-2016 | 04:58 PM
#162
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From: ɹəpun uʍop 'ʎəupʎs
06-02-2016 | 05:23 PM
#163
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From: Anaheim
I was a little bit concerned about if that was actually true, when Colin in post #399 on the other thread said:
"I have pulled off a number for secondary belt changes, and upgrading to the PKT black version."
That statement really raised my eyebrows, when it was written, because I knew that Ken and Colin are good buddies.
And....
....that statement sure sounds like one of the main "insiders" is changing the gold for the black, preemptively.
06-02-2016 | 05:44 PM
#164
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That's what I thought was the case, that an update kit made the gold bracket the same as the black bracket.
I was a little bit concerned about if that was actually true, when Colin in post #399 on the other thread said:
"I have pulled off a number for secondary belt changes, and upgrading to the PKT black version."
That statement really raised my eyebrows, when it was written, because I knew that Ken and Colin are good buddies.
And....
....that statement sure sounds like one of the main "insiders" is changing the gold for the black, preemptively.
I was a little bit concerned about if that was actually true, when Colin in post #399 on the other thread said:
"I have pulled off a number for secondary belt changes, and upgrading to the PKT black version."
That statement really raised my eyebrows, when it was written, because I knew that Ken and Colin are good buddies.
And....
....that statement sure sounds like one of the main "insiders" is changing the gold for the black, preemptively.
