A Lambda system, O2 sensor system, fuel emission control system or whatever one likes to call it, is not “engine size or engine code” specific. Yes, different engines use different ways to do the same job, more or less, but having one or not having one is not really a matter of engine size or code. It is also not a “power killer” as some may like to believe. No, race cars do not have emission systems, but power robbing is really not the reason why. Your plan as you stated it was to restore the car, I didn’t see mention of building a race car or street racer? And even if you do want a nice little street performance car, the emission system will not hinder you in any way (in fact the system can be used to help).But depending in which engine stays in the car? When the GTI engine is ready, would it need Lambda?
As you indicate above, there are 90amp alternators which fit your car and they should be enough for almost any situation, I would think. I don’t see the need to re-invent the wheel as they say or start machining custom one-off parts (for a restoration project for sure) when what you need is already there. I have also seen for sale up-grade kits for alternators, maybe there is one to increase the 90amp to some level higher, don’t know.. . . . Bosch sells High Output Alternators, (150-200 AMPS!) but they do not fit this car. . . . I have also read a smaller/better pulley will help an alt to work more efficiently . . . I can machine aluminum with Carbide router bits to build a mount. . . The ones in the junkyards here are JUNK. I could find a new model, I'm sure, (90 AMPS) but what part # am I looking for?
I would not go so far as to claim all “junkyard” alternators are junk. I have had some real nasty looking alternators that I cleaned up, installed new brushes in and mounted that are still working perfect to this day. Unless there is a part inside bad, like a diode or break in the wiring, there is not much to go wrong with them, they just look dirty. I can get you a part number or two for a 90amp but the sticker has to be still on the alternator and readable too.
I know and do understand that this is your project and your money, but why keep looking towards fabricating or machining things? Can the car be driven currently or are you in a rush to get it on the street? Are you really thinking restore the car or just get it back into shape to drive and look good? These throttle bodies and manifolds should be easy and cheap at places like Ebay or the sales pages here. Using factory parts makes fixing and replacing all that much easy later if need be. A "stage III" manifold, sorry if someone looses a sale, is really a waste of cash for what you are doing. What exactly does "stage III" mean too, or is it one of those common sales tricks like camshaft or ignition adds? If a stage III manifold does all that much, just how then will it work with an un-modified engine? Kind of like installing a sport cam on an engine with a tiny restricted exhaust, right?It looks like I will be able to put one of the trigger pins onto the BBTB (where it is marked Pin), and just have to machine a holder for the micro switch. Piece of cake. cannot find one of the suggested intake manifolds. Maybe a junkyard in the city will have something . . . and I cannot just drive to the city at the moment. . . If not, a stage 3 intake manifold has a re-welded plenum and ported runners. and 89 Cabriolets are nowhere to be found in my area.
I am not trying to change your mind or make you think as I do. I do not want you to change your plans for your car to meet my plans or goals for my cars, past or present. What I do want to maybe do it get you to think before you jump into something. Does it fit into my plan? Will it really make things better and if so how? How can I do this more simple or do I have to make modifications or do fabricationing? Where is my money best spent? I have spent so much money and tried so many usless trick modifications over the years due to advertisments and hype talk. So please don't feel I am against you when I attempt to turn you away from the smae mistakes.