Converted FI to carb-need to adjust carb

[mpernice]

I'm sure this has been asked a lot, but the following is my situation.
Some background.
I spent the winter converting my 77 Bug from FI to carb. I have an EMPI electric pump and regulator (for carbs). I have a dual vacuum distributor, original to car. I installed a PICT34 carb. Valves are gapped. Points .016”. Timing: there’s’ 2 tick marks on pulley. I have it so the right one lines up with case seam. (timing with gun).

When I start the engine and the choke is closed engine runs at 1500 rpm. It keeps running as long as I don’t touch the throttle. If I do, I need to rev the engine to keep it at least 1000 rpm. After 4-5 minutes with engine warm, the engine ides at 1000 rpm and runs. If I rev it as if I was driving and then let up on throttle it usually dies.
My guess is it’s an air-fuel ratios thing. I need to understand how to adjust the carb. If I hold the ‘butterfly flap’ down, the engine will rev at 1500 rpms.

[Chip Birks]

Doesn't get asked a lot over here. In fact most of us that are actively on this forum spend obscene amounts of time doing the exact opposite. We are regularly ditching carbs and going efi.
I wish I had the carb knowledge to be of any help. Hopefully someone will speak up though.

[V8Nate]

If I remember correctly the 34 pict needs to be adjusted the same as a 30/31 carb. The screw on the throttle lever needs to be backed completely off until the butterfly is completely closed then turn it in so it barely cracks open, this makes it so you do not engage the progression ports(make sure you hold the high idle cam in the open position) then you can mess with the two screws on the drivers side of the carb, the big one is basically the idle speed it allows air to bypass the throttle plate for idle. The small screw is what determines your air/fuel ratio. Turn the big screw out a couple turns and it should idle pretty high then when the engine is warm you can turn the big screw back in to drop the idle. If it starts stumbling and wanting to die then mess with the small screw to smooth out the idle. Continue to screw in the big screw to get your desired idle speed and adjust the small screw to get the smoothest idle(turn the small screw slowly to allow time for the engine to react to the new setting) I usually start turning the small screw in until the idle gets slightly rough then turn the screw out an eighth to a quarter turn. You will also have issues if you dont have proper intake heat and your intake ices over. This should get you close as long as your ignition is set properly and of course the valves are adjusted. Hope that helps you out

[V8Nate]

I would also advise to get a dwell gauge or borrow one if you are planning on using points

[mpernice]

Thanks V8Nate. I have a tach/Dwell gauge. The dwell is at 50 deg. Throttle lever screw was backed out then turned in a 1/4 turn. The engine does run smooth. I'll try to adjust the two carb screws as you suggest. Thanks for the help.

[mpernice]

Doesn't get asked a lot over here. In fact most of us that are actively on this forum spend obscene amounts of time doing the exact opposite. We are regularly ditching carbs and going efi.
I wish I had the carb knowledge to be of any help. Hopefully someone will speak up though.

Chip
I had the stock FI system up until this past Nov. I always had minor issues even though I always checked vac line (biggest culprit) and even replaced components. By mistake I severed the FI harness and gave up on FI. I had a carb'ed engines in the past and remember that fuel & spark is needed. Just need to re-learn the typical maintenance of point and carb adjustments.

[Bruce2]

The dwell is at 50 deg.

The spec is 47º

[Tietz]

Chip
I had the stock FI system up until this past Nov. I always had minor issues even though I always checked vac line (biggest culprit) and even replaced components. By mistake I severed the FI harness and gave up on FI. I had a carb'ed engines in the past and remember that fuel & spark is needed. Just need to re-learn the typical maintenance of point and carb adjustments.

The stock FI systems are notoriously ridden with issues, are they not?

[mpernice]

Biggest issue is maintaining the vac lines. Any leaks will cause problems,

[Jim Ed]

What kind of carb is it?
If it is a 34PICT3 this would help:
http://vw-resource.com/34pict3.html