34pict3 not adjusting properly! Help a VW newbie out!

[Jakeroz]

Hello all! I am currently bringing a 1973 thing back to life as a favor for a friend. Brand new dual port 1600 with pertronix distributor (SVDA), Bosch epoxy blue coil, pertronix plug wires, new plugs, brand new 34pict3 from Jbugs, electric fuel pump at 3 PSi, all the good stuff. I've been fighting this car for months now and I'm at a loss... Timing is set to 30°BTDC without advance at 3000 RPM, and 40°BTDC with advance. I have the carb set to all the basic settings and follow all carb adjustment posts to a T but haven't found one experiencing my issue. When I set the RPM to 850-900, I turn the volume mixture screw out from the base 2-1/2 turns and the RPMs drop, I thought they were supposed to increase? When I screw it in, they increase but no matter what adjustments I make between the screws I still get spitting and sputtering out of the exhaust and sometimes the carb "wheezes" like it's lean. It smells and looks like it's running rich still, and no matter where I've set the carb when I think it's correct, it still spits and sputters under quick hard throttle. I've tested for vacuum leaks and have none. The car drives fine in first, but when I shift to second it spits and sputters and wants to die, it just won't drive in second. I'm at a loss, can anyone lend me some knowledge?

[FJBLF]

I think you have too much timing...
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1972 VW 181 SAFARI 1500 cc GRB Trans-axle

[germansupplyscott]

[kenj06]

[germansupplyscott]

I set the timing both at idle and max all in. Sometimes you have tweak either/or to get the engine to run well at all rpms. One thing you have to make sure of with a vacuum advance distributor is that the vacuum advance is fully gone at idle.
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SL

[SilverThing]

I would suggest starting at the 2.5-3 turns and turn in to see if you can get the fastest idle speed. The dealer manuals don't specify which direction you should be turning from that starting point to achieve fastest idle. I even checked the German manuals and they seem to concur, but my German is admittedly rusty. After achieving the fastest idle, they suggest that you then turn back until idle drops 20-30 rpm (again turning back doesn't specify in or out). I find that the turn back is a pretty small adjustment.

One thing I have found with idle adjustments is to take your time and give the engine a few seconds to react to your changes. I go a 1/4 or an 1/8 turn at a time and wait to listen to what happens.

Another thing I have done with idle adjustments is having as much electrical stuff on as possible as a worst case. Lights, gas heater, wipers, radio: all on. Getting it to idle well at 900 with everything on does lead to the idle rpms to be a little high with everything off (usually around 1000), but it makes for a better driving experience for me. Here in the PNW it is normally cold, dark, and rainy most of the year so I rarely have the heater going without the wipers and the lights on at the same time. I noticed my electrical load at idle went down a bunch when I changed my headlights to LEDs. Idle still ends up in the high 900s for me.

Idle adjustment on my 1835 is a bit of a dance between the timing (I run a DVDA), the volume screw, and the bypass screw. I suspect the reason is there is too much cam in the engine for the single carb (possibly an engle W100 cam). There is definitely a sweet spot where everything comes together nicely. Outside of that sweet spot and it can get really frustrating keeping the rpms around 900, with the timing where it is supposed to be, and adjusting the mixture.
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