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[Horizonblue]

I'm in the process of doing an EFI conversion on my 1976 Euro 924. Until now the main focus has been on the hardware that's needed for the conversion. Nothing electrical yet. Ah, well I have found a distributor from a VW Golf 3 1.8 that fits perfect and borrowed some injectors, for fabricating a fuel rail.

Anyway, I would like to have one big throttle body, instead of the old 2-stage. I started out making plans for how to mount a throttle body from a VW Golf 3 GTI 16V on the original intake manifold. But it didn't seem like it could be done without welding a thick aluminiumplate onto the manifold. My TIG welding machine can only weld steel. Another problem was clearance for the fuel rail.

But it came to my mind one day, that I had seen a turbo intake manifold with a single throttle body. And to my luck, this one suddenly came on Ebay



I bought it.

Another guy on the forum has put a turbo intake manifold on a N/A head, and it was not just a "bolt on and go"

So I was quite interested in getting the manifold in my hands, and seeing how much trouble we were talking about.

Here is a template I made some time ago, when I was working at a factory that had a water jet cutting machine, laid on the mounting flange.



As you can see, the intake holes are actually the same, but the lower mounting holes are offset 4 mm(0.158 inch) and the upper are offset 3 mm (0.118 inch)

Now what? It was out of the question to make the holes oblong, way too much material to remove, especially on the lower holes.

After some thinking, this solution came to my mind. Offset-studs.



They are made from a standard Metric 8 mm bolt, where the head has been cut off.



I made a tool, in which to press these bolts, they are heated prior to pressing, otherwise the tool is destroyed, since it is not hardened.



The tool is made from whatever I had in the workshop, stainless steel was the hardest I could find

Thread is cut after pressing.

4 long and 4 short studs are made and mounted in the head. The holes in the head are countersunk a little, and the holes in the manifold are countersunk in one direction, to accomodate the offset piece of the stud.





And on it goes.



The original N/A intake boot, fits the new throttle body.



A stainless steel tube fits the other end of the boot. This picture is taken before the holes in the intake manifold were countersunk. You can see a gap between the manifold and the head, the manifold could not go further than this, because of the missing countersinkings.




And now there is ample space for the fuel rail.



Mission completed; I now have one single throttle body and plenty space for the fuel rail.

And now on to the other part of the EFI conversion, finding the right injectors and sensors, finish up the fuel rail etc
_________________
Euro 924, 1976

"If you can't fix it, don't break it"

/P.G. Andersen

[932kiwi]

Well done, brilliant.

[peterld]

Amazing.......
_________________
80/81 932/8 ROW

[gegge]

Weired solution, but it works and I like it!
_________________
Carl Fredrik Torkildsen

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