Best carb / distributor setup for 1970 1600 SP

[Housefull7]

I was hoping to get some suggestions on the best carburetor / distributor setup for my bug. It is a 1970 1600 sp. Right now it has a 30 pict 3 carb with a 009 dist with electronic ignition. It has the classic "flat spot" and is horrible in the low end. It runs the best once you get up to cruising speed.

[Marc]

I suspect you have a preheat problem. Still have a stock muffler? If not, did you drill out the heatriser passages (almost all aftermarket exhaust systems ship with them either undrilled or with only tiny holes). Even when they are drilled, they don't provide as much flow as a stock muffler, but it's normally adequate for a singleport. It's also not uncommon for the preheat pipe on the intake manifold to get plugged up with carbon. It should be warm to the touch along its entire length after just a few minutes of running if there's good flow through it. What aircleaner are you running? A stock one with a functional warmair pickup system is best. I prefer the ~1972 style with an integral wax-pill thermostat, no cables or vacuum hoses to deal with like the others have. http://images.thesamba.com/vw/classifie ... 938811.jpg
With the engine off, remove the aircleaner and observe the stream coming from the accelerator pump nozzle when you pull the throttle open. It should be a good solid stream that starts after only a few degrees of motion, and ideally it'll be aimed so that it just misses the side of the carburetor venturi.
While the advance curve of the 0 231 178 009 distributor may not be ideal, it's adequate for a singleport - I've known hundreds in the last 30 years without that complaint, even in the cool/damp Seattle climate. Set the timing to 30-32° maximum (with a strobe, at ~3000RPM) - that'll typically yield 10-12° BTDC initial, plenty for decent "step-off" unless the manifold's cold or there's an accelerator pump problem.
Dualports have a larger intake tract which reduces flow velocity/vacuum; this puts the fuel-air mixture closer to the "dew point", when the fuel condenses on the manifold walls creating a momentary lean condition and the resultant flat-spot - that's why most complaints about the 009 originate on dualport engines. It's not due to any inherent problem with the 34PICT-3 carb, although it's common for people to tamper with the carburetor in an attempt to solve the symptom.
Because of the smaller intake on a singleport, they're much less susceptible to the "syndrome" - if there's a flat spot, it's usually due to a simple accelerator pump issue or lack of preheat.

[Aynthm]

A 30 pict 1 with a 205K does it for me.

[Marc]

A 30 pict 1 with a 205K does it for me.

What's the 10-digit Bosch number on that distributor? I don't recognize "205K" but suspect it may be a big-can 40HP distributor (c1964/65). Those are absolutely horrid once worn - with the slightest vacuum signal they'll go to full advance. Wonderful for eliminating flat spots, but disastrous to the pistons/rings. The sound of marbles rattling in a coffee can under low-RPM load is a bonus

[bigmeat]

I use a 30 pict carb and timed it to 28 degress full advance other day.
boy what a difference it made. Ran like a scalded dog. Not bad for 1641 single port. I am with marc check your preheater tubes.

[Redandgifted]

Hi there, I have a 1969 Beetle that has a 1640 single port motor with a 30 pict 1 Solex. I'll try to be brief, but what I did was put a Petronix SVDA electronic ignition in it and it ran, but I think I've messed things up. I didnt know the carb dist matchup couldnt read the signal so now I need to know what distributor should I use? My bug is currently not running and am going to go back to points with vacuum advance only. Whats the difference between a 205T or 205k? Is it just any dizzy with vacuum advance? Any help would be appreciated! Thanks!