hacker-pschorr

I don't recall Ken ever saying that either, but plenty of other people have which is how internet "facts" are born......

IMO the hydraulic portion of the Porkensioner should be replaced at a regular interval with everything else.
They do fail, I've seen it on the Audi's they come factory installed on.

ROG100

With every iteration of the belt I recommend changing the tensioner - low cost part and you are already in there.

69gaugeman

Your kidding, right? Ken's tensioners have been on for how long? A couple of years? How many were sold? A few hundred? As compared to 50,000+ of the factory tensioner over MILLIONS of miles?

I never said that Ken's tensioner were better or worse. They certainly are untested over the long term and statistically are unproven. Because you like the 'idea' and it seems 'better' does not make it so. The reality is the stock system works. Follow the maintenance procedures and your engine will last MANY hundreds of thousands of kilometers. Been true since they made them, true now.

If you sleep better at night with the Audi tensioner on, then have at it. You are free to do so. But to spout unproven claims and ad untrue fear mongering irritates me.

Even in the flat world they managed to sail around just fine. Never fell off either.

the flyin' scotsman

no joke...........Kens system has been installed on a great many 928s, both of mine included with 10s of thousands of miles/kms with zero issue. Theres also the fact, as you state yourself, the tensioner is used OEM by Audi on many models with 100s of thousands of miles of proven reliability.

Indeed we are free to make choice; thx for reminding everyone

RKD in OKC

I'm not against the Porken tensioner. Just that I chose to keep the stock tensioner because it keeps the toothed belt warning function because it's warning would have averted the valve crash had I and my mechanics believed it and looked farther into the cause of it going off.

ROG100

Just for the record and for 69guagemans info - I have sold hundreds if not way over a thousand PKensioners over nearly six years and many owners are on their second iteration of the TB change and beyond. Were do you get your information from?

The PKensioner has been in use before I started to sell it so it is well proven.

I have personally fitted over 45 PKensioners to customers and my own cars. My own GTS has covered over 60k miles on a PKensioner and is on the second iteration of the belt.

Please check your facts.

Imo000

I'm one of the well documented cases where the warning system saved my bacon. I did a full write up with pictures. The warning system kicked in way before any other signs showed up and when an engine is spinning at 2500rpms, every second counts. It's irrelevant how many other manufactures have a warning system. We do and we should be extremely thankful for it. Its just a matter of time before siezed water pumps will start taking out the Audi tensioner 928s and then a shift back to the stock tensioner will start. The disabling of the warning system is the ONLY reason I kept the OE setup.

69gaugeman

Sorry Roger, but those are insignificant number for statistical analysis. Maybe a thousand units vs 50 thousand original. 60k is the longest period on record so far. Not good enough Roger. Show me you verified numbers and then I will say that it is as good as the factory. It is not possible to yet have numbers that prove it is better than the factory, and at best anecdotal that it is as good.

Trust me, this is what I do for a living. Stats on automotive measurements. I work in the automotive engine and transmission measuring field and have been to hundreds of plants and have seen first hand how this works.

Using your facts, you changed the belt before 60k. How much before sixty? Doing that on the factory tensioner would as much insure not having one on the factory system break either.

I check my facts. It is why I say what I do. I know about this stuff because I eat , sleep, and breath it. It has been my job for over 20 years.

If it is indeed better I would also say that. But it is not in the numbers. When it is I will agree. But the factory system works. Always has , always will if you do the prescribed maintenance. THAT is what I am saying.

the flyin' scotsman

oh man..........I was going to write about the Quality Assurance lab I managed for the worlds largest Telecom provider and go on and on about stats and how they can be managed but why.

Use the OEM, we don't mind...........we're using the Porkensioner.

69gaugeman

I have no problem with that. Just don't say it is better and that the stock system is no good. That is all I am saying.

dprantl

It is better than the stock system. We are talking about *belt tensioners*. The porkensioner is a better belt tensioner system from an engineering standpoint, period. It keeps the belt in the correct tension range regardless of temperatures. It also dampens belt flutter which the stock system does not do. How can you say it is not better when, for example, the stock system *disables* the warning at startup because when the engine is cold it is not able to properly control belt flutter even with that band-aid idler pulley in place?

With regards to maintenance, everyone is free to check their belt as often as they wish. The porkensioner does not magically stop you from being able to do this. In fact, I check the belt tracking regularly even though I have the porkensioner installed.

I agree with you that the belt tension warning system is a good thing to have if you are going to experience an impending catastrophic failure. But let's use the same data methodology here... 1) what is the probability this will happen and 2) what is the probability that when it happens, the warning system will save your engine? I would say extremely small, and them quite small.

I understand your point of view, but if everyone thought like this about everything, we would still be using vacuum door locks. It's difficult to have innovation when you need to wait for volumes of data in order to accept something new, especially when it is very easy to see from an engineering standpoint that an alternative newer system is superior.

Dan
'91 928GT S/C 475hp/460lb.ft

uncre8tv

Jesus. Everyone pick their gamble and go their ways. This thread is almost as stupid as when the vendors start sniping at each other.

portensioner = more consistent belt tension at the expense of a warning.
stock = warning light and original engineering.

pick your poison and live with it, we're not getting anything useful out of this discussion here.

the flyin' scotsman

For the original poster:

if you choose to replace all the gears, the water pump, the belt and the tensioner then use fresh coolant changed on the regular interval you will enjoy many trouble free miles and years. Inspect the crank and oil pump seals and the camshafts.

I wouldn't shop around on Ebay for the parts..............call Roger or another dedicated 928 Porsche supplier, they'll sell you the correct parts for a reasonable price. Its the cost of owning a rare Porsche sports car.

Good luck

snoz

RKD. Which tensioner did you have in place when your cam broke?

SeanR

He had the factory system. Been stated several times.