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I had a 34ICH on my Sonett for a while (until I got a 2bbl) -- it's a good match for the V4 engine and you should not be having this type of problem if everything is set up correctly. As you've found, there is no adjustment for accelerator pump stroke, but none is needed; worth checking pump operation to make sure diaphragm is not torn, as someone else described, but as it's a new carb you'll probably find that isn't the problem either. Here are a few guesses:
-- Vacuum leak: This is my #1 guess for two reasons: you said it doesn't stall in the full-choke position, and you said you tried to adjust the air/fuel mixture (with the screw on the side, I assume?) "without notable success." That mixture screw only affects the mixture at idle, not at higher RPMs, but when the engine is idling there should be a LOT of change in the idle as you adjust the screw in and out. If there isn't, it usually means air is leaking in somewhere other than the carb and leaning out the mixture, which can cause stumbling on acceleration among other problems (putting the choke on full richens the mixture so can mask the problem.) Most likely spots for the leak would be at the gasket between the carb and the intermediate plate, and between the intermediate plate and the manifold, but there are other possibilities too (e.g. power brake booster hose connection to the intermediate plate, or vacuum line from carb to distributor vacuum-advance chamber. Oh, yeah, you did plug up any unused vacuum ports on the carb, didn't you?)
-- Wrong jet: The 34ICH has a removable main jet that can be replaced with various sizes to accommodate different engines and states of tune. If you bought your carb from a generic supplier rather than a SAAB specialist, it may have come with a jet that isn't ideal for the V4. I'm not really a jetting expert, but my 34ICH (which I got as an NOS kit that had been sold specifically for Saab V4 use) came with a 165 main jet, so I would guess you wouldn't want anything smaller... if you've got an MSS exhaust or anything else that improves the breathing you might want to go with something a bit larger, maybe a 175 or 180. How do you know which jet you've got? Take off the top of the carb by removing the screws (be careful not to bang the float as you lift off the top), unscrew the jet from down in the bottom of the float bowl, take it out, and look at the number stamped into the side. (The numbers are milliliters of fuel flow per second or something like that.) If you don't have the right jet or want to experiment, you can order other sizes from Performance Parts Warehouse (http://www.webercarburetor.com) for a few bucks apiece.
-- Anti-diesel solenoid: This is the weird little electric gizmo that sticks out the side and needs to be connected to a wire that supplies 12v when the key is on. Its job is to cut off the fuel when you switch off the key so the car won't "diesel" (keep turning over even though the ign is off.) If you don't have a good steady electric supply to this, it could be making the car stumble.
There could be other things, too, but you might as well start with these. Don't give up, because your car SHOULD run really nicely with this carb on it.
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