Hi, I am a professional certified mechanic, with an engineering background, and 35+ years experience. I will do my best to assist you. Also keep in mind I don't know if you are a pro or a novice so we may have to fine tune the answer. Feel free to add any additional info you feel is needed as we go on. Always keep in mind that I am here to help you with any questions.

The single port heads cant take advantage of larger carbs, like the ones you want even if you could bolt them up. So if you are after more power you really need to go with a dual port head. I have owned, and built many VW engines, and what I would do is to find a 1600 dual port engine and use it as the basis or your engine build. There are other advantages to the newer engine, and you can install lots more performance parts, and carbs onto the 1600 dual port. More power, and more reliability, it is really a good move. Also it bolts right up to your VW. If you have any more questions, as always, I am here to help. Good luck with it, have a great day, and Thanks for using Just Answer.

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