New Val in the collection

Hello
My father used to be a real Classic Car lover and had a lot of cars. After he had none for 23 years now and had seen how this hobby inspires me and saw my restorations, he came into consideration to get a Classic Car again.

After a long search, someone from our Valaint Club came forward to sell his, as he was no longer able to do so due to health reasons.

So I went for a look. It is a Swiss Valiant. Here they were built and sold as Chrysler, but they match the Plymouth. Unlike in the US, this one still has a 170 engine. A904 column Tranny. The car is really in great shape, except for the engine compartment, where they did some ugly welding, but that can be fixed as soon as I'm done with my 65 Wagon.

The car has only one problem. When accelerating a bit harderä (When starting at a road intersection, the pedal about halfway down) it chokes and sputters. But at normal gentle acceleration, everything is fine.

The fuel pump, the Intake, The lines are in order. No dirt. The Carter BBS has been overhauled by him, but I think that might be where the fault lies.
Idle is also good.
What else could it be?
Should I swap to Holley?
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