Larry Velk

I used Jean-Louis' homemade "Kempf" and did the recheck when my back-ordered "real" K-tool came from 928 Inter. They agreed - which shows a skilled engineer like Jean-Louis can even make his own tension tool. (Actually the recheck was a bit looser, as you would expect, center window, 32V). I've used the 9201 on my 951, with gauge bar. It was consistent and not too bad to use, but there is a bit more room on that car.
Of some interest, I've done and supervised literally hundreds of "Hooke's Law" experiments - the concept upon which especially the "Kempf" depend. Even with students doing the experiment the results are very consistent - that's why they call it Hooke's Law, not Hooke's Guess.

Tampa 928s

So where should the bar be set on the window I was advised to the high side at the top of the notch. Is this wrong I have my cam cover off now to replace the air pump belt has 50 miles on it should I redo it ?

a4sfed928

I remember in training class the Porsche rep noted that once you calibrate the 9201 you should place an "X" on the side not touching the Calibration bar. This was to ensure the same side of the pads were used to tension the belt always. Supposedly if you were to flip the pads between readings they would show different values.
I did not read all the listed posts so if this was already mentioned Sorry.

Bill Ball

Erkka:
That is a great post from 2004 and Jay's subsequent reply answers some of the other questions, such as whether the reading should be higher for 32 vs. 16 valve.

atb

Ed,

Your reading on the Kempf tool is the accepted "normal" for the 32v motor.

I've never used the Porsche factory tool, but my understanding is that the factory tools are very sensitive to correct positioning, causing different folks to get differing readings on the same car. The Kempf tool is much more easier to use, and much more consistent. One thing you do need to make sure is that it is clean and lubed (as opposed to dirty and grunged up), THAT will have an affect on the reading.

mark kibort

yes, the porsche tool takes some technique to use correcly. But , when you do it correctly, you know it.

my kempf tool was calabrated to be like the others here has found. 5.0 is about 2/3s the window on the tight side.

mk