73 transporter engine problem

[red39715]

My 73 transporter I believe it has a 1800cc engine is cutting out when I get to high speed or going up a hill. It kind of acts like it is running out of gas. I have never worked or owned a VW air cooled engine before so I have no real knowledge. The carb appears to be an after market one not the original. It has been running ok up until lately. It runs fine at low speeds and idling just not at freeway sppeds and up hills or under load. Any help would be appreciated.

[Robertas33]

I think you need to sell your car.