This may be a longshot but what diameter tires are you running on the back? I have run up to 27" diameter tires on 16" rims and the stumble definitely increases with larger tire diameter. 1st to 2nd gear is the worst.
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This may be a longshot but what diameter tires are you running on the back? I have run up to 27" diameter tires on 16" rims and the stumble definitely increases with larger tire diameter. 1st to 2nd gear is the worst.
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Sidecar I just have the tins on top of the jugs and of course the fan shroud. Is there anything I am missing?
VW driver I am running 16 inch rims and the tires are 26" tall. Mine seems the worst from 2nd to 3rd and 3rd to 4th. I have kits for the carbs so I am going to put them in. I would like to know the stock jets for the Empi 34 epc so I can check them when I have the carbs down. Whatever they came with.Originally Posted by vw driver
Sounds like ur missing all the lower shroud and thermostat.I believe those carbs are idle 52 main 130 an we went 57 an 140.I u haven't done so already. Drive it where the problem is worst,kill the engine check the sparkplug color.Too rich will make it hesitate also.Idle air screws can help some if u keep it on the rich side.Just check that the plugs aren't black.
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Is there more tin to bolt on the bottom of the jugs?If so I will get some.I wonder if all the jetting has a number on it so you will know what it is. I know the low speed jets do but don't know about the rest. I am tearing them down today so I will find out I guess.
The problem is in the 1000 to 1600 rpm after first shifting into the next gear.Let me know on the tin if you can. Thanks
Sounds like idle speed jet.You could try 1/4 at a time on the idle mixture screws,if it feels better go another 1/4 if it feels worse go the other way.This process is gonna b trial an error anyway.I may be able 2 email pictures of what I have 4 lower shroud but not 2 handy with computer stuff.
Stock 165R15 VW tires are about 241/2" tall, that is what the gear ratios in the VW trans were designed for. Yours are taller. I have found that with oversize tires that I had to wind the engine out higher before changing gears so it wouldn't lug which can cause a stumble.
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I have a 52 idle speed jet. I put a kit one of the carbs today. Going to do the other tomorrow. I think that is what the carb comes with. I'll just keep folliing with it. If you can send me anything on the bottom tin I would appreciate it.Yeah, VW driver I may need to wind it up a little more. I am pretty bad about shifting too early. What kind of rpm would you guess I would need to shift at. Thanks for the suggestions.Stock 165R15 VW tires are about 241/2" tall, that is what the gear ratios in the VW trans were designed for. Yours are taller. I have found that with oversize tires that I had to wind the engine out higher before changing gears so it wouldn't lug which can cause a stumble.
Both of my VWs have older engines so I try to keep them under 4000 RPMs, 3000 RPM to 3500 RPM shifts mostly to make them last.
I don't think a 52 is gonna do it for ya.Just for you're information the jet sizes run off 1mm so a 52 is 52 percent of 1mm.So 52 percent of .039 is a.020 drill.don't want 2 argue drillin jets.maybe it will help ya.If u send me an email i can reply with info on shroud.If you jet fat enough you'll probably b okay with jetting.
VW Stock Jets
Stock jets on a 35 PICT 3 are 55 and 127.5. Just re-jetted ours to 60 and 130 and got rid of the stumble. Finally!!Now...on to other bugs to work out!! LOL!!
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OOPS!! Meant to say a 34 PICT 3!! Duh!!
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Thanks for the help. I have a 160 air corrector, 130 main and a 52 idle jet. I don't know what increments they have on the idle jets. I don t mind buying more idle jets if that's what it takes. If I increase the idle size should I leave the main alone. We used to have a hobby here you could buy the pin drills in thousand increments but it closed. Wonder if I should try a 55 idle jet or maybe something little larger.Stock jets on a 35 PICT 3 are 55 and 127.5. Just re-jetted ours to 60 and 130 and got rid of the stumble. Finally!!
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OOPS!! Meant to say a 34 PICT 3!! Duh!!
Normal ranges for 34 carbs are 130-145 main and 55-60 idle jets. Your 'lag' spot in the power curve is generally caused by running too lean at some spot in the transition from idle to main. With dual carbs, I would not be afraid to go to the max on idle (~60) and maybe 140 on main jetting. As you've found sometimes the only way to find the best performance is a bit of trial and error (of course, with the jets running $6-10 apiece now you want to hit the right combo ASAP).
There also is a trick that can help the flat spot that is usually limited to when using an 009 distributor with a stock carb. If your carb butterfly has a small hole in it near the center area (I'm not sure on the dual 34 carbs), it is there to increase the air to fuel ratio at low and transitional speeds (i.e., lean it out). Why the carb manufacturers chose to use such a 'bandaid' fix is beyond me when they designed the carb. But, by soldering closed that hole you are richening the low speed mixtures across the board. As stated it often removes the flat spot caused by the slow to advance 009 dizzy, but might work for you if you expend other tuneable alternatives.
As to just finding a quick way to test if you are truly sluggish because of lean mixtures, just adjust your choke(s) to stay closed slightly (maybe 1/4) when running and see what happens. That will make for a richer mixture and will possibly validate that you are indeed running too lean in the lower power curve. Temporary adjustment, don't leave them that way even if it runs beautifully.
Just my no-risk ramblings. No blame if I'm wrong and no charge if I'm right.
Have you set the volume and bypass screws on the carbs? Here is a good link explaining 34pict3 adjusting.
http://www.vw-resource.com/34pict3.html#carb
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