[T3] Dual Carb Shift Vacuum

[Craigs List]

Guys,

I have a little bit of an update. I decided to dive into drilling and
tapping all 4 manifold ports today. After work I got the passenger side
manifold drilled and tapped. I will finish the drivers' side manifold
sometime next week. I have few plans over the next few days that will keep
me from finishing.

I went on a test drive with just the one manifold ported with BOTH
cylinders tapped. You  can tell that it has helped quite a bit. With the
erratic vacuum signal that I was getting with only the one cylinder tapped,
it would downshift hard when you were coming to a stop. Just porting the
second cylinder on that side has taken that away. It rolls to a stop and
downshifts like it should. It is almost unnoticeable.

It sill does not want to shift into third, but it does shift a lot smother.
I can't wait to get the other side tapped and a balance tube ran. I am
happy with what it did so far. I will let the pictures do the talking.

In this first picture, you can get a feel for what I wanted to do. I could
not think of a way to get this to work,.

http://one4house.com/images/manifold6.jpg

Because of room constraints and such, I decided to go with the setup you
see below. It ended up working out great.

http://one4house.com/images/manifold1.jpg

http://one4house.com/images/manifold2.jpg

These last 3 pictures are the manifold bolted into place before I put the
carb back on.

http://one4house.com/images/manifold3.jpg

http://one4house.com/images/manifold4.jpg

http://one4house.com/images/manifold5.jpg

I will post some more pictures next week when I get the other side done.

Adam


On Wed, May 7, 2014 at 10:42 AM, Jim Adney <jadney at vwtype3.org> wrote:

> On 7 May 2014 at 8:37, Craigs List wrote:
>
> > The only thing that scares me about this is that I had a balance tube
> > between the two manifolds when I had the 34 ICT's. I had this same issue
> > with those carbs. and not wanting to shift.
>
> I have no idea if this will actually cure your  problem. Once you get
> off the beaten path, you're either on your own, or you're looking for
> someone who has already blazed this particular trail for you. What I
> can be sure of is that this should give you a better vacuum signal
> (more pulses per engine cycle and lower average vacuum.)
>
> > I am more than willing to put a vacuum port on all 4 barrels. I am just
> not
> > convinced that it will make that much of a difference. Here is a picture
> of
> > the setup I had before.
> >
> > http://images.thesamba.com/vw/gallery/pix/1127904.jpg
>
> Those hose sizes look fine. Note that the OE AT engine breastplate
> has a cutout at the bottom so that the VM hose can go straight down
> toward the VM. That shortens the hose, which should speed up the
> response time slightly.
>
> You also want the vacuum ports in the manifolds to be nearly as large
> as the hose ID. If they are small, that will slow down the response
> time.
>
> --
> *******************************
> Jim Adney, jadney at vwtype3.org
> Madison, Wisconsin, USA
> *******************************
>
> _______________________________________________
> VWType3.Org mailing list - type3 at vwtype3.org
> http://lists.vwtype3.org/listinfo.cgi/type3-vwtype3.org
> Contact gregm at vwtype3.org if you need help with the list.
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.vwtype3.org/pipermail/type3-vwtype3.org/attachments/20140514/a2c4a578/attachment.htm>