Unused vacuum port on distributor???

Hello guys (and girls?). I am a newbie and I have a question:

I have a 74 Standard Beetle with a solex 34PICT carb and what looks like an SVDA distributor. The car runs great!!! I have no complaints whatsoever considering the car's performance at idle, at speed, and off the low end. All are fine. I am confused though. There is no vacuum line connected to the vacuum canister on the distributor. How is the timing advancing sans the vacuum source? I haven't driven a bug in more years than I'm willing to admit, but last time I dealt with these sweet little engines the timing was vacuum advanced. What's this new technology that I'm dealing with?

Thanks for your help. Jim

Reply to
fenderjw
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Jim,

welcome to ramva.

I hope your vac ports are caped off on both. Either way, you will need a metal line that has a u-bend in it in order to restore your vac adv. It is connected to the thickest brass fit on the carb pointing out the back. I think there might be up to 3 ports if I am not mistaken.

you can find a lot of good articles for tune-ups and everything else on

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I tried to locate a diagram that identifies vac ports, but was unable, double check the manual for location of the port.

Hope this helps, Anton

fenderjw wrote:

Reply to
anton

Thanks Anton. What I was really asking is this: The car is running great as is. I was wondering if maybe some sort of upgraded ignition parts/system had been installed on the car that had replaced the stock setup. I realize that this sounds like a silly question, but I haven't been around vee-dubs in a few years and I'm wondering what could have replaced the old tried and true svda/34pict combo that I'm familiar with?????

If there is a brain box or some other sort of upgraded electronic ignition system installed, then I haven't found it. Is it possible for this old fat chick to run so well without the benefit of vacuum advanced timing????

Thanks for your help. Jim

ant> Jim,

Reply to
fenderjw

There are some ignition systems that would use distributor body as a pickup which you could identify by flat cap with a small wire coming out of instead of a cap with 5 holes. In which case it would be truly sad to see svda distributor body being used for this. If you still have original cap and all spark plug wires then I would say vacuum tube is simply missing. try taking some pictures, posting them on the net and reply back with the links if you can.

Anton

fenderjw wrote:

Reply to
anton

Sounds perfectly normal for an SVDA. The very core feature of them is DUAL ADVANCE (DA). They provide both vacuum advance for load sensing, AND mechanical (centrifugal) advance for rpm dependent advance.

You are running solely on rpm advance, i.e. in the "dumb" mode.

You would get better throttle response and fuel economy if you hooked the vacuum hose back up. Plus smoother take off at low rpms, like when driving in heavy stop&go traffic. It gives you more advance (read:more power) when it is safe to do so, and when the conditions do not favor that much advance, the distributor falls back to centrifugal advance only. (Wide open throttle)

Jan

fenderjw wrote:

Reply to
Jan

hi why do you need metal line? I have 4 MM rubber line does it make a different?

thanx

nachche

anton =D7=9B=D7=AA=D7=91:

Reply to
nachche

OK, now I remember! S- (Single) V- (Vacuum) D (DUAL - that makes sense!!!!) A - (Advance) Thanks for reminding me Jan. Dont ever get old. The second thing that goes is your memory. I forget what the first was :)

Jim

nachche wrote:

Reply to
fenderjw

Reply to
anton

oh and I guess since it's metal it won't collapse from vacuum, simular to as braided break hoses idea, the only difference is you have positive presure in break lines so hose won't swell up and you get firmer breaks.

Ant> lasts longer, don't take my word for it check this out

Reply to
anton

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