dprantl

Haha, wow. My reading comprehension is just fine, because you said exactly:

In this case, "It" in the "It is superior" statement refers to what was written in the previous sentence, which was "The factory tensioner".

And the tracking fails on the stock tensioner due to the use of plastic bushings that wear over time. The hydraulic tensioner has no such failure point.

Furthermore, don't kid yourself if you think you will be as lucky as Imo if your water pump freezes and the tension light comes on with the stock tensioner. By the time most people will realize what is happening, it will be too late.

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

69gaugeman

Well all my english classes say that 'It' refers to the current sentence. Not the one previous. But hey, english was not my favorite subject. There are many who know better than me. If that is the rule I read wrong all the time. As I have been taught, that sentence says the superiority resides in the tension warning light, not the overall design. My thoughts on the design of the Audi tensioner as a tensioner has been stated.

My stance is there is no need to change the design of the tensioner. It works perfectly. Yes it needs to be maintained but any of them do (the roller on the Audi tensioner can cause tracking issues too, just not as likely). I have never seen a properly maintained Porsche tensioner fail. Greg Brown uses the factory tensioner. And while there may be personal issues between Ken and Greg, he wouldn't hesitate to do something to make his engines better. His reputation rides on it.

69gaugeman

There are many reasons why the tracking goes off. The tensioner just happens to be the most common. I like to think I am more attuned to a vehicle than most. I am sure that if I had been smarter and torn the front end apart and not assumed the tension was low because it settled in or stretched when the tension light went off, I would have saved a rebuild on the GT. With Ken's it would have blissfully tensioned until it exploded.

PorKen

Internet theater. It's all good.


With as new components, a functional warning light, and routine service, the belt may be kept tight on the gears by the factory tensioning system.


For all the reasons mentioned in the dissertation above, the belt on a performance engine is better managed by a PKT, 04 cam gears, and a Racing belt.

69gaugeman

This is what I am saying. The factory system works fine.

That was a Gates promotional brochure, not a dissertation, in case you were wondering. Good reading of course, but the factory system has dampening as well.

Don't get me wrong, Ken, I respect what you do. I just prefer data to speculation and conjecture. I also don't believe in change for change sake.

By the way, I use the 32v'r tool to set my timing.......

Cosmo Kramer

Timing belt failure, from my reading here, has mainly come from three sources:

1. Water pump failure. Factory warning system will give you a heads up (a very short one).
2. Shoulder bolt failure. Factory warning system will give you a heads up. Bolt is not required with PK tensioner so that failure is eliminated.
3. Oil pump gear comes off. Factory warning system will give you a heads up ( again, a very short one).

I have never seen a failure from an old belt or under tensioned belt. It is always a mechanical device that fails which in turn destroys the belt. The PK tensioner in one of these failures will just keep sucking up the slack until it runs out of adjustment room and/or the belt snaps with no warning to the driver.

The PK tensioner has its advantages, no need to manually adjust, less stress on gears and rollers and more even, steady tension at varying temperatures. It all comes down to your risk tolerance.

SeanR

Not sure where you Canuks get the idea that the PK will continue to tension until the belt snaps, just how much movement and pressure do you think that piston has? 6 inches/2 feet/100 ftlbs? Not happening.

Cosmo Kramer

It will continue to tension until it is at the end of its adjustment range, which is I believe around 11 mm. On a stalled wp pulley that is enough to snap the belt. In Imre's case he got a warning and he got it shut down in time with the stock tensioner.

I think it is a great system for tensioning the belt, but you have to be confident in the rest of the components in the system as they are usually the ones that cause the failure, not the tensioner.

the flyin' scotsman

I would suggest most Cannucks have the PK installed and love it.

In my experience the oil pump gear remains in place when the nut is torqued properly with some blue loctite added.

Regular maintenance of the coolant system eliminates the pump seizing concern. Check the pump when replacing the belt at the recommended interval, 100k kms or 5 years, whatever comes first.......your level of maintenance may vary.

I have new cam, crank, oil pump gears with a new water pump, Gates belt and PK fitted to my GTS. Have approx 1000km on the car since with no concerns. Will report back in 6 months or much later

BTW I also added new coolant hoses, fluid and cleaned the rad while it was out. Car is 20 YO and is now good for another 20.

Adamant1971

Mine got a new pump, gates belt and a pk tensioner. 12k later no issues.

The main advantage of the pk is automatic adjustment unlike the manual adjustment of the stock tensioner.

Granted if your stock tensioner is good there is no need to change it. But if like mine completely shot, the pk tensioner is a modern maintenance free alternative.

I like it.

Now lets get this thread back on topic an stop the tensioner pissing war.

😱

PorKen

Sorry, I avoid tensioner threads these days (no need), but I often do my best thinking in the 15 minute post edit window.

The dissertation is my post, seven years in the making. The brochure merely supports my thesis.

It has taken many a tensioner thread and some arguing with folks for me to understand the concept behind the old belt tensioning systems vs. the new belt control systems.
To get past the 9201 stretch measurement to see that the overall goal was and is to maintain control of the belt between the crank and 1-4 gears.


The pre-stretch model works in a narrow temperature range, but, because it is an indirect method, it is weak at the extremes, hence the pulleys, and the startup delay on the warning light.

The control model directly manages the belt as it rolls past. Besides working at all temperatures/rpm, it can use lower overall tension, and it also has the benefit of not allowing belt flap.

PorKen

And...to reiterate...the reason I initially posted, the stock tensioner cannot be used with the Racing belt, as the Racing belt does not stretch.
(Which is good, if you like consistent cam/valve timing.)

928 at last

Update??
Saw a late model S4 in town today.......