timing belt tensioners / belt stretching

["harris,michael" <michael@domain.elided>]

<< Why is it that so few understand much about the tensioners that Alfa sells? 
To begin with, the belts DO NOT STRETCH! >>

Hi:
>From my experience, I disagree with this - new belts do stretch a bit once
initially used.
As example. the Porsche 944 requires that the belts be re-tensioned after
about 2000 miles after new belts are installed.  Since Porsche did not make
allowance for the tension to be increased automatically (and thus
compensate for this stretching), this must be done manually after the belt
has been run-in for a few thousand miles.  I think the Alfa system is much
better since it will compensate to some degree for the stretching ('cos
it's spring-loaded) - but I usually also re-tension my GTV6 belt after 2K
miles just to have the optimal tension on the belt (I'm referring to the
'new' thermo tensioner of course).  When doing this re-tension job, I've
noticed that the belts are quite a bit slacker than when first installed -
ie. the reference pointers no longer line up as they did when the belts
were first installed.  The belts do not seem to stretch further once this
2000 mile (approx) mark has been reached.

Cheers
Mike
1985 GTV6
http://www.gtv6.org

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