Compression method suggestions, test procedure step by step

[Phil@isham-research.demon.co.uk (Phil Payne)]

In message <3471872B.B2E60A8D@poboxes.com> Gerard writes:

> > I have it as 7.8:1, changing to 8.4:1 with the 1989 model change after VIN
> > KN038268.  In the UK ur-quattro, essentially the same engine achieves 8.6:1 -
> > my own engine measures at 10.6:1 or just above in all cylinders.
>
> Did they only change the pistons when going from 7.8 to 8.4 or 8.6
> to 1? I assume everything else such as timing and valve head goodies
> were kept the same. Or were a whole lot of extras changed when they
> changed the compression?

I don't know exactly what they changed, because I don't have a set of
200TQ spares microfiche.  I imagine one of our US lister friends does.

> Quicky: VIN is read off the metal ID plates at the B pillar, right?
> If I could quote my VIN would it then be possible to have someone
> indicate the compression they had on that model?

VIN plates are in different places in different markets.  It's stamped
into the top of the firewall, and on the id plate wherever that may be.
On UK cars, it's inside the engine bay at the right end of the firewall.

> 10.6:1 ?? non-turbo,  right?

No, turbo - but a low-quality gauge.  I wouldn't be surprised if the
gauge (it's a Gunsons gauge, for those that know the brand) was 15%
off.

--
 Phil Payne
 phil@isham-research.demon.co.uk
 Phone: +44 385302803  Fax: +44 1536723021