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Fri Oct 23, 2015 8:42 pm

Needs some help guys
I have 1776 motor with a 34pict 3 carb. motor is stock, except it is opened up to 90.5 for a 1776 and 009 dist. Timing is good and it idles great. motor seems to run well but, is very flat when i take off. second gear is very bad. If I rev the motor, it is a little better.
My question is, what should I jet mt carb too, to fix this problem? Do i only need to touch the main jet? I know dual carbs or a nice weber, would be the best answer, but money is tight.
Thanks

Sat Oct 24, 2015 4:36 am

I've always felt the 009 did not respond well with a 34 pict-3. I have had good luck with the SVDA distributors.

Sat Oct 24, 2015 4:37 am

Do you still run the stock aircleaner with hot air from the cylinder head or have you got an air filter on top of the carb, letting in cold air which causes the fuel to fail to evaporate properly?

Sat Oct 24, 2015 6:15 am

Buy some extra jets from the classifieds, get a metric pin vise drill index, and experiment with some different sizes. I would say you may end up with a .60mm - .65mm idle jet up from the .55mm. You may not need to open up the main jet, but you'll need to find drill bits around 1.30-1.35mm if you want to experiment with it. Start with the idle jet, and readjust your idle/mixture screws on the drivers side of the carb with each change.

Sat Oct 24, 2015 6:25 am

Sorry,
No air cleaner is not stock. Paper after market

Sat Oct 24, 2015 6:30 am

So, main jet and idle
A buddy of mine has some pin drill bits, I will give it a try

Sat Oct 24, 2015 6:54 am

Im runni g a 34pict on my 1700 build. Jetted 130 main and 65 idle. I feel that the 65 idle is a little fat though I am trying to bring it down to 60 idle. I have a size 70 air correction too.

Frank

Sat Oct 24, 2015 6:54 am

Just work with the idle jet first. You may be able to get 90% of your hesitation out with that. You could also open the accelerator pump jet (the brass faucet looking thing at the top of the carb throat) to .60mm to help with the additional vacuum of the 90.5mm pistons. It's ideal to have a metric set, but if your friends pin vise set is not metric, just convert the sizes.

.60mm / 25.4 = 0.0236

Sat Oct 24, 2015 7:13 am

Sounds to me like have the 009 combo 34 carb which is a poor combination.
Yes you jetting may need some fiddling with. Source out a German
0231 170 034. I bet your engine will run better.

Sun Oct 25, 2015 5:48 am

Yes, get the right distributor for the carburettor. I keep not understanding why people "automaticly" lean toward a 009 as soon as they do anything.
*Next ditch that stupid aftermarket aircleaner and replace it with a late model 1600 unit. Make sure the vacum vents work in the filter. THEN you can start jetting.

T

Sun Oct 25, 2015 6:58 am

What I don't understand is why people keep saying you have to have a vacuum advance distributor with a 34 pict 3 carb on a modified engine when it is the jetting in the carb causing the hesitation, and has nothing to do with the distributor. VW set up a vacuum advance distributor, and the stock jetting in a 34 pict 3 for a 100% stock engine. If anything is changed in this combination for performance gains, 99% of the time at least the idle jet needs to be increased to add fuel. I've tuned engines modified with a header or 87mm piston/cylinders only that had flat spots WITH the correct factory stock working vacuum distributor because the engine needed more fuel. And the shop I worked at has tuned 100's of engines, modified/not modified, with 34 pict 3 carbs, and 009 distributors that ran as smooth as the stock engine with the vacuum distributor.

The OP stated he wanted to spend as little money as possible. For those that do run vacuum distributors, and have bought a new one within the last 5 years, which one do you buy? How much was it, and is it still available now, or is it like everything else, did it get replaced by an inconsistently performing reproduction? And for those that "sourced" a used OEM Bosch vacuum distributor, how much was it, and how many of them did you have to buy at swap meets/classifieds before you found one that had the 40 year old vacuum diaphragm still working? And how long did this 40 year old diaphragm continue to work after it was installed from sitting in a milk crate in someone's garage for the past 20 years? If the OP has one of the poorly made reproduction 009's that is contributing to the issue, than it is the inconsistency of manufacture, not because it has a mechanical advance.

I will agree you may be able to squeak out a mpg, or two more with a vacuum distributor, but why tell the OP he needs one, when he can tune the mechanical advance distributor he already has to to run 99% as good as if he had a vacuum distributor?

Sun Oct 25, 2015 7:20 am

The German SVDA 034 do show up from time to time here in the classifieds. The last one that came to my Post Office Box was fifty three dollars. The vacuum pot works, they are available by the way. It spun free and weights are functioning. That makes the total number of 0231 170 034 distributors in my possession four.
The poster will have to do some additional tuning for sure. I wish VW would have made a 38 mm single center mount carb.

Sun Oct 25, 2015 7:43 am

gt1953 wrote: The German SVDA 034 do show up from time to time here in the classifieds. The last one that came to my Post Office Box was fifty three dollars. The vacuum pot works, they are available by the way. It spun free and weights are functioning. That makes the total number of 0231 170 034 distributors in my possession four.....

"They are available" as in, they show up in the classifieds from time to time, or are you talking new? If you're talking new, please post some links? Of the four you have, are they on four running engines, or are all four in a milk crate in the garage for a rainy day? If they are on running engines, how many miles do they get driven a year?

Sun Oct 25, 2015 8:57 am

:) Why not just buy a NEW 043-905-205N from Mexico that is the same as the last 74 bug from the assembly line before the 75 FI engines.

There is bound to be a few NOS sitting around somewhere but more then likely slim chance so Mexico does have a copy available since I have access to them

As for the main jet issue a 130 drilled out a wee bit will help there for the 90.5 pistons along with an adjustment of the pump stroke on the Gen/Alt side of the Carb.....would take care of the hesitation lag.

I did that on many of my engine builds and never messed with the idle jets.

Sun Oct 25, 2015 9:14 am

The Oh thirty four (034) can be had here and it appears they stand behind the product.
http://vwparts.aircooled.net/category-s/343.htm?se...amp;page=1

Sun Oct 25, 2015 10:27 am

[email protected] wrote: What I don't understand is why people keep saying you have to have a vacuum advance distributor with a 34 pict 3 carb on a modified engine when it is the jetting in the carb causing the hesitation, and has nothing to do with the distributor. VW set up a vacuum advance distributor, and the stock jetting in a 34 pict 3 for a 100% stock engine. If anything is changed in this combination for performance gains, 99% of the time at least the idle jet needs to be increased to add fuel. I've tuned engines modified with a header or 87mm piston/cylinders only that had flat spots WITH the correct factory stock working vacuum distributor because the engine needed more fuel. And the shop I worked at has tuned 100's of engines, modified/not modified, with 34 pict 3 carbs, and 009 distributors that ran as smooth as the stock engine with the vacuum distributor.

The OP stated he wanted to spend as little money as possible. For those that do run vacuum distributors, and have bought a new one within the last 5 years, which one do you buy? How much was it, and is it still available now, or is it like everything else, did it get replaced by an inconsistently performing reproduction? And for those that "sourced" a used OEM Bosch vacuum distributor, how much was it, and how many of them did you have to buy at swap meets/classifieds before you found one that had the 40 year old vacuum diaphragm still working? And how long did this 40 year old diaphragm continue to work after it was installed from sitting in a milk crate in someone's garage for the past 20 years? If the OP has one of the poorly made reproduction 009's that is contributing to the issue, than it is the inconsistency of manufacture, not because it has a mechanical advance.

I will agree you may be able to squeak out a mpg, or two more with a vacuum distributor, but why tell the OP he needs one, when he can tune the mechanical advance distributor he already has to to run 99% as good as if he had a vacuum distributor?
I´d say that sounds very wrong, - unless that distributor was worn or had other issues.
Stock carb, - stock matching distributor. Can´t be easier than that.
_ Naturally the jetting needs to be right. With the 009 you can of course jet it so rich that it wohnt stumble, but is that the right way to do it (?)

Sun Oct 25, 2015 4:59 pm

In my humble experience with the 34 pict and 009,
By the time you open up the low-speed jetting enough to get it pulling nice down low,
It gets dirty/stinky/rich enough to be a nuisance.
Also has poor fuel mileage around town...

The correct original distributors were taken off of the car enough that there are actually a lot of them left lying around.

I have taken 009s off and replaced them with various SVDA and DVDA from different Aircooled cars, even busses and type 3s or..?
And, in all cases, they worked a LOT better than the 009 with a stock carb.

Maybe there are some tuning experts out there that know a lot of things I don't, but for me, just throwing fuel at the problem was a poor solution, and a false economy after you paid for all that gas..

Sun Oct 25, 2015 6:01 pm

thanks for the good advice guys.
I think I want to stick wit my setup this year and maybe in the spring, get some duals. buddy of mine is trying to convince me, to get a progressive. but for now, i just want to tune the 34.
I am going to order a rebuild kit and a couple of jets and see how that works.

Mon Oct 26, 2015 4:25 am

If you think the 34 is troublesome, don´t go the progressive route. It´ll oinly be more complicated.
T

Mon Oct 26, 2015 6:55 am

Had a progressive and what a pain that was. You would be better off with the correct distributor. In addition to that you may even get to use the same distibutor with dual carbs. I do.