Intake manifolds

[jadney@vwtype3.org (Melissa & Jim)]

>From: Steven Ayres <comwest@well.com>

>In addition to the small split balance/vacuum port, I have a pair of 
>cylindrical lugs about 13mm in diameter that could be drilled through to 
>create what appear to be secondary intakes of some sort, at 90 degrees 
>to the primary intake and past the split. There are airways about 3.5cm 
>long cast inside, and these are what we'd have a problem flowing.

This is not one of my areas of expertise, but I have often heard that it is 
counterproductive to try to get intake manifolds smoothly polished.  
Something about turbulence being important to encouraging the mixing of the 
intake gas/air.  This is as opposed to exhaust ports where laminar flow 
minimizes heat loss to the walls.  Made sense to me, but I have nothing to 
back it up with.  What do others think?

 The 
>manifolds are steel, and to weld them up smooth would require too much 
>blind internal work to be practical. I've thought about filling them 
>with epoxy or something, but my engine man is dubious about having so 
>much foreign material that could crack off and get sucked into the 
>cylinders later. I'd be interested in hearing how you'd handle this.

The Devcon stuff might work, but I agree with your reluctance to put it in a 
place where such a failure could be disastrous.  How about drilling/reaming 
the passage from the outside and fitting a pin which could be ground to a 
smooth fit on the inside and tack welded on the outside?  A taper pin might 
be best.

>But then there's the question that will probably apply to a few other 
>members of the list: Does anyone sell aftermarket intake manifolds for 
>T3s? 

I thought Berg sold several types.  What carbs are you using?  Could you 
just use the '67 OE DP manifolds?

Jim
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       Melissa Kepner                                    Jim Adney
       jadney@vwtype3.org              jadney@vwtype3.org
                             Laura Kepner-Adney
                             Madison, Wisconsin
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