Porsche Enthusiasts Club Forum

I've a 944 2.5 86 NA registered Feb 86. Oval dash.
It has the water pump update kit and Gates belts, eccentric tensioner, no spring tensioner too early

I'm confused about the reference values for new belts tension on first install

If I look in the w/s manual it says one set of values - page 15.3 cambelt 4+/-.3 New 2.7 used ,page 13.3 Balance belt 2.7+/-.3 new or used. It does not mention the new style belt 18mm width

If I look in clarkes garage he says a set of different values ( 4mm for camshaft 2.7 when used (same as w/s man) and 3.5 for balance belts) he then gives 2.7 for the 15mm wide balance belt and 3.5 for the 18mm one with no values for 'used'

Also I read the balance belt always feels looser than the cambelt and should not be the same tension as the cambelt

Any wise advice? does the used balance have a 2.7 tension even if 18mm wide after 1000 miles?

The belts sound noisy ie whine but I believe thats always true of new belts and settles down after re-adjustment after 1000 miles?

Usually when they whine, the belt is over tightened! If it stays like this it usually destroys the bearing in the water pump!!

Answering my own questions after a bit of searching

for a pretty definitive tutorial, with numbers!, go to

http://www.rennbay.com/belttutorial.html

is good enough for me ...............................

Yes that is a good link. I was confused by your question as you were quoting differnt methods of measuring the tension. I have a Crikit here as well as the Arnworx kit. The Arnworx looks quite fiddly to use TBH & I'll probably use the Crikit.
One point I woud say about the Rennbay instructions, he talks of rocking the cam backwards & forwards I was always told that you should never turn the engine backwards when adjusting cambelts.