Made a very similar post about 5 or 6 months ago, but things have moved on a little since. Situation however remains that I'm fitting a MK2 Golf 1.8 8v EV based engine into a MK1 that previously had its original 1.8 8v DX. Before the decision to do this was made I'd already invested in new injectors / fuel lines etc. for the DX, so I'm now committed to using those. As the EV head is set up for shrouded injectors / different holders / lines, I'd have needed to make a few minor changes so the DX stuff fits. That's basically just blocking off the inlet pipe on the rear of the EV head and using the later holders so that the shrouded function is effectively done away with. However I've since found the injector holders pictured below. They seem to have been fitted very briefly on early MK2 GTI's before the later brass holders with additional lower plastic covers and injectors with top-hats were introduced. So it's looking like I may be able to utilise the injector shrouding effect of the EV head with my non-top hat injectors and lines after all. Question is where did the EV get it's air for the shrouding from? You'll have to bear in mind I'll be using the non-shrouding MK1 intake / airflow meter and associated pipework, not that of the shrouded MK2 EV's, I'm presuming at this stage there'll be differences / pipework / connections I'll not have but was hoping to find a workaround if possible. EV holder with fine threaded injector and top-hat... Shrouded course thread injector / no top hat in early MK2 holder...
it was fed by a T piece inline with the AAV, the 2 unlisted part number are for a restrictor pushed up the hose and a hose from inlet to T piece:
Cheers... does look doable, based on that. So I'm looking air syphoned off from just prior to the throttle body (the rubber boot), but before it enters the AAV. Will have to get the MK1's pipework out and get my head around what I do and don't already have.
Some nicked inter-web images of the MK2 EV set up... with the MK1's manifold / AAV being the reverse plus back to front it'll definitely need a bit of custom pipework /fettling, but unless there's something I'm missing I don't see why it'd not be possible.
ah bugger you have a MK1 keep forgetting ETKA isnt very clear how its piped, this random image from teh internets suggests here, ignoring carbon canister: and this audi image seems to back it up:
The Audi set up makes it look very straight forward, just a pipe from the bellows before the throttle body into the nipple on the head. I've an Audi 80 intake here somewhere, may even have those bellows and hose on it! The screen shots are again from the inter-web, but you can see the pipe (25?) that goes to that 4 legged connector in the schematic, I'd be just ignoring it and all the other gubbins, going straight into the bellows.
Surprising the different versions there are of the rubber bellows when you start to look at them. Settled on the example below with the 2x outlets (the original only has the one) which appears to be from a very early MK2 GTI (# 027 133 649). Some others have outlets in places that don't suit the MK1's metal pipe you see in the images or else have a third conjoined outlet that'd need bunging, no point complicating things needlessly. This particular one came with it's pipes and connectors, which as luck would have it turned out to provide a second, and probably easier way of tapping into the air supply than I was initially thinking. Both the green and blue connectors are described as restrictors, not connectors... not sure why they need to be so, but presumably required otherwise a regular connector with the same internal diameter as the pipes they're joining would have done. I'm probably going to go for the stubby T piece connector way of doing it, that set up just needs a single length of pipe from the blue restrictor to the nipple on the head (each have the same outside diameters) to complete whereas using the green connector'll also need some sort of a reduction / adapter piece to do the same job as it and the nipple are different diameters... still very doable if needed, but starting to become unnecessarily complicated. If you're thinking of doing something similar to introduce air shrouding be aware that the rubber 'T' piece is still available new (# 027133367A) and not for a great deal of money either, however the blue restrictor is looking like it'll be lot more difficult to track down (new at any rate).
I don't know if it would help you, but I bought a mk1 inlet manifold for a vacuum pipe connection. Now I have got this, would any of these parts be of use to you. I can get better pictures if you want
That's very geneous, thanks. Hopefully I have all the shrouding bits now, though the car's very far from having its engine back in / running so always possible something'll need replaced... might be messaging you if that happens! From memory, the 5th injector and Auxiliary Air Valve are the same on late MK1's as your early MK2 so will be useful to you as spares. They may look grotty, but it seems like they've still their original pipes / connectors suggesting they've not been open to the elements. May well be spotless on the inside. That three legged rubber junction piece on the right in the second image is expensive new, don't believe it's on a MK2, but even so if yours isn't cracked worth sticking up on eBay? Don't try taking out the angled connector or one way valve, will probably split the rubber... guess how I know! The throttle body'll probably come up well too.