vernier pulley?

[Steinbru@vnet.ibm.com]

Here's a post from the vw list.  Help me out here, how does a vernier
pulley work?  I picture something that varies valve timing: from the
crank or at the cam?  Would it be static?  Could it be varied w/o
removing the head?  I haven't seen this discussed here before, would it
be applicable to the I5?  Could it be a low cost source of some extra
ponies for my 5ks (5deg of ignition advance made a noticable
difference)?  If I find the source, I'll post it.  --Gary

--REFERENCE--------------------------------------------------------------------
Date:    Sun, 26 Oct 1997 19:01:36 +0200
From:    Duane Walker <caver@PIXIE.CO.ZA>
Subject: 16v mods

Hi all
I finally replaced my stolen Golf with a 89 16v Jetta Cli as usual I was
unable to leave it alone for long and started out by fitting a set of 256
deg Scrick cams with a vernier pulley, these raised my peak power from 98kw
to 107kw and put a dent in the midrange which adjustments to the cam gear
brought back.
Last week I fitted a tubular 4 into 2 into 1 manifold and a very free flow
exhaust of my own design which increased the torque by 10nm  to 168nm at
6400 rpm and peak power to 118.5kw at 6800 rpm which is not as peaky as it
sounds, as the torque curve is pretty flat.
I also fitted my Haltech E6A engine management system which I am busy
fabricating a fuel rail for hope to have this running in a week or two.
cheers for now.
Duane Walker
Johannesburg
South Africa
"You can never have enough horsepower"
16v mods