3B water manifold/head info requested

Bernie Benz b.m.benz at prodigy.net
Mon Oct 14 18:56:05 EDT 2002

> From: <auditude at cox.net>
> Bernie Benz b.m.benz at prodigy.net wrote:
>> I have a loose 3B water outlet manifold, 034 121 193A, that is destined to
>> go into my 7A upgraded to 3B externals project, that I could loan to you for
>> a short time to use as a pattern.  Adapting the 7A head to accept it would
>> require boring the additional 3 20mm water passage holes and their
>> respective single tapped mounting holes for each.  The additional water
>> passage holes are O-ring sealed with the O-ring positioned on the mating
>> manifold projections fitting into the head bores, so will only require a
>> straight thru bore.  This water manifold would interfer with the 7A intake
>> manifold, why it is not used thereon.
> Okay, so I already have one of the 4 holes?  The water manifold adds three
> more holes, and one of the ports on the manifold mates with the existing hole
> I have?  If so, that is very good as it will help determine placement of the
> remaining holes.

> I appreciate the offer, but let me see if I can locate a stock manifold first.
> Thanks for the part number too.
> I was thinking I would really prefer a head to measure over the manifold,
> since I could have the manifold installed on the head in some slightly
> incorrect location.
> Hey, what's that funky-shaped hole on the intake side of the head, at the
> bottom towards the middle/front?  It's flat on the bottom and is almost
> pyramid-shaped, but the two top lines are concave.  I don't have the head in
> front of me right now, maybe it's the water port (not thinkin' so).
You are describing the single water outlet cast-in hole in the base casting.
The 7A uses a single mating water outlet adaptor casting sealed to this
machined surface, (the same surface mating with the intake manifold), with
an o-ring and held to the head with the three hold down bolts at the apexes
of this triangular hole.  This hole is located between #2 and #3 inlet
ports.  The 3B adds the 20mm ports between the other inlet ports, and the
manifold reduces this triangular port to 20mm for equal outward flow between
each cyl head.  Because the manifold bolts up to the head with the same 3
widely spaced bolts that hold the 7A adaptor, it would be a simple task to
accurately locate the additional holes required with a pattern made from the
3B manifold.
> Bernie, when are you going to have this procedure done to your head?  Do you
> have a shop picked out already?  Are you getting a valve job done as well?  I
> would like to find a shop to do mine, but I'm scared to go to any old machine
> shop.  I'd prefer a shop with Audi or VW experience.  Also, I think the cost
> can have a pretty wide range for this type of stuff.
I hadn't considered the problem in depth, thinking that the heads were
identical and expecting that the manifold would just bolt right up to the 7A
head.  Thanks for the enlightenment, and additional work required.

> It would be pretty reassuring for me to have the shop that did your
> conversion, do my conversion.  No need for me to blaze trails with a separate
> shop, I think I'd rather pay shipping.  But then again, if they take and keep
> good measurements of what they do, then maybe that could be used at another
> shop without much risk.
> Thanks,
> Ken
> From: <auditude at cox.net>
>>> I would like to find out as much as I can about the water manifold on a 3B
>>> head.  Does anyone have any dimensions or pictures of the manifold and the
>>> ports in the head?
>>> I am thinking of converting a 7A head to have 4 water intake ports like the
>>> 3B
>>> head.  Currently it has one, and people say that the (main/only) difference
>>> is
>>> that the 3B head has ports for the water manifold.
>>> I have decided that I don't have to modify the head to actually use the
>>> factory manifold.  I can probably get away with machining some port and
>>> threading in some aftermarket fittings and create an external manifold that
>>> would do the same thing.  I would just need to understand where the
>>> underlying
>>> water passages are.
>>> If I go the path of fitting a factory 3B water manifold to the head, then
>>> this
>>> information could be used for other 3B owners wanting to be able to use the
>>> more plentiful 7A heads for repairs or upgrades.
>>> So, any help would be appreciated.
>>> I doubt anyone might have one, but if there are any junk 3B heads around
>>> that
>>> I could borrow or have to take measurements, that'd be great.  :-)
>>> Thanks,
>>> Ken

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