I asked that question just a few days ago.  I have a 2.1L WBX that came from
a Syncro.  The advice i got was not to bother with the 2.1L system... but if
that's the case why did VW change so much in the first place?  I'd like to
keep the oil cooler.  If I end up retaining my '84 cooling system I'm going
to install and aftermarket oil cooler from Bus Boys.

So.. here's my thinking.  The '86 coolant pipes, the ones that run the
length of the van, are shorter than '84/85.  If you look at your firewall
the pipes stick out and that's where the rubber hoses clamp on.  In an '86
the rubber hoses go through the firewall.

Here are pics of my 2.1L with the cooling system:

http://i16.photobucket.com/albums/b7/misterpolak/WBX_transplant/WBX01.jpg
http://i16.photobucket.com/albums/b7/misterpolak/WBX_transplant/WBX02.jpg

As in an '84/85 there are two large hoses that connect to the radiator and
two smaller hoses that connect to the heaters.  As you see on an '86 and
newer, one heater hose must cross over the transmission to the passenger
side to hook up to the heater.  It APPEARS that the steel or plastic pipes
your '84 is using would need to be cut a little shorter to interface with
the hoses from the 2.1L cooling system.

I'm going to pull my engine first and then try to test-fit the hoses in
place to see if it all match up.  I'll have more pics in a few days.  The
engine should be out Thursday.

On Mon, Jul 7, 2008 at 10:34 AM, Jamie Fitterer <fittdog8848@hotmail.com>
wrote:

> I am thinking about upgrading my coolant system on my 84 1.9L to the 86-91
> system.
>
> ANy thoughts on whether I should do this or not?  I see taht GoWesty does
> it on all their Vans and was thinking maybe it would be something good to do
> while I have Van in to get its Fuel lines replaced.