Date: Fri, 1 Mar 2002 03:54:38 EST
Reply-To: FrankGRUN@AOL.COM
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Frank Grunthaner <FrankGRUN@AOL.COM>
Subject: Re: Golf motor with Diesel Mounts intake manifold questions
Content-Type: text/plain; charset="US-ASCII"
David,
Sorry for not getting back to this post earlier but I had to finish a design
for a microanalytical laboratory to analyze organic compounds in melted water
surrounding a cryo-robot we are proposing to profile the Martian polar cap!
I just got back to this question tonight and would like to offer some
information from the perspective of my notes and the warm study (containing
the computers).
In a message dated 2/23/02 9:57:45 PM, vanagon@VOLKSWAGEN.ORG writes:
<< Volks,
There are quite a few of you out there who have installed an 85 - 92 Golf /
Jetta motor into their Vanagon using the Diesel motor mounts. As most
people know the intake manifold will not fit as it will hit the drive side
wall of the van. The common solution to this was to pound a dent into the
side wall to make it fit.
The question that I have is: How deep of a dent did you have to make into
the side wall?
Well, actually I didn't make a dent, I cut a hole! After pounding away for
some time, confronted with visions of brutality and the wimpiness of my
efforts, I went out and rented a serious disk cutter. The problem was that
the "dent" requirement was right at the edge of the top of the frame rail. My
measurements suggested that I was going to have metal to metal contact at
that point within the oscillation range permitted by the motor mounts. So I
cut a 50 by 100 mm slice out of the engine firewall area, and I notched the
frame rail cutting a segment 25 by 25 by 100 (or so) mm. I then cut and
welded in a piece of angle iron into the frame notch and added a sheet of 1/8
inch thick viton sheet to cover the hole after the engine was in place. This
eliminated any air or water introduction to the compartment other than was
the case before the surgery. I also painted the exposed metal ends with black
epoxy marine paint in lieu of the corrosion threat. Note that my numbers are
the same as Alistair's probably due to the fact that those were the numbers
he forwarded to me so many years ago.
What I am thinking of doing is modifying the intake Golf manifold by shaving
off 12mm to 13mm off of the surface that attaches to the head to give me
that much more clearance against the side wall. In doing this I will have
to build up the aluminium around the intake runners where it enters the head
as 13mm back from the original surface is quite thing and may not make a
good air seal.
Comments, suggestions and measurement as all welcome!
The cut 'em off and reweld the flange approach is an interesting one but it
seems very labor intensive and therefore costly at least in the LA area. But
another suggestion.
As I have been making a variety of pieces for my Audi 3A Turbo
adventure/project, I have been accumulating a depressing number of poorly
sorted parts. As part of this cache, I have an intake manifold from an 87 CIS
Golf, two Audi 3A intake manifolds, two 3A exhaust manifolds, a Golf
turbodiesel exhaust manifold, a Quantum turbodiesel intake and exhaust
manifold, etc,. etc., etc. In studying these pieces several points are
obvious:
1., The intake manifold and 8V head for the Audi 3A are clearly superior to
the VW 8V non crossflow units (not a positive statement about the cross-flow
head and manifold, I just haven't looked at them). This superiority comes
from the repositioning of the fuel injectors back into the intake manifold
from the head, and the larger area of the intake ports. The fuel injectors
are almost perfectly oriented to the intake valve.
2. The intake manifold for the '87 VW Golf CIS car extends 7.480 inches from
the surface of the head. That is, if you took a plane perpendicular to the
intake manifold surface at the head, that plane would contact the outermost
surface of the manifold at 7.480 inches (190 mm.). The edge of the throttle
body is towards the head by about 1 inch (will measure exactly this weekend).
3. This same projection on the Audi 3A manifold is just 5.510 inches (140
mm). The Audi manifold has two inches less projection out from the head as
compared to the VW unit. The Audi intake should clear the engine compartment
by just around 1 inch.
4. Finally, the height of the top of the intake manifold castings above the
main intake manifold flange bolts is exactly the same for both manifolds.
5. My suggestion: Use the 3A 2.0 L block for the best conversion. It's intake
manifold will accept CIS injectors for the superstitious CIS troops, and the
modified injector insert I posted some time ago will permit the use of
Digifant injectors, fuel rail and connectors.
6. If this is unsavory, I note that the pre '88 Audi 5 cylinder engines use
the same intake manifold geometry as the 3A, but have the older port
cross-section as used by VW for all the 8V non cross-flow heads. These
manifolds are very cheap in the bone yards. Cutoff the 5th cylinder feed and
weld a blanking port in place.
7. I was also told the intake from a VW Fox would fit w/o bashing. (did not
verify this). However the Fox manifold is said to flow poorly with a
significant power reduction.
Hope this helps,
Frank Grunthaner
