I have a progressive weber with a scat intake on what is supposed to be a 1776. it starts greats and idles great, when you drive it it spits and sputters when you mash the gas. Its seems like if you drive it and only push the pedel half way so only one butterfly opensd if runs kinda right, but when you open both it falls on its face.
Ive cleaned it and adjusted the air/fuel mixture to about 2 turns out and it still runs the same ive tried turning the mixture scew every way possible and i still cant get it to take the gas like it should, it seems if you baby the pedel and dont try to slam it down itl take the gas but i know its just not right. So, im thinking i need different size jets or a hotter spark.
any help is much apperciated.

Im having these same symptoms creech told me to check float levels i have a 1915 with dual empi 40 carbs on it he. Told me to shake the back of my buggy and see if there is a change in idle when you do this because the level of fuel can be to high and splashing out of the bowl into your intake and causing it to run to rich i adjusted mine some already but finally went down today and tinkered with it more and still needs the float set lower hope this helps some

ive been riding it around for about 2 weeks and on a rough trail the idle doesnt change, i had a solew that would do that on a rough trail or if you shook it and the float was set like 2mm off but this weber isnt doing that.

check your jetting on the progressive. Then check for crap in your accelerator pump. Is the problem worse in the cold weather and do you have manifold heat to intake? Checked you distributor to see if your mechanical advance or vacuum advance is working.

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Water Cooled Consortium, Chairman of the Build (Former AC purist)

I would start checking ignition sounds like when you put it under load its not firing. if cap, rotor, plugs, wires and points look good change the coil

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If it ain't broke ill fix that

Thats kinda what i was thinking, but I had a pict 34 solex on it and it ran perfect. So i dont think that the coil could be going bad maybe just weak to begin with. all the problems have came with the weber being put on. Im just not sure on what to do with the jetting, i can let you know what size they are tomorrow and also check the accl. pump and no it does it when its warm out to

that solex didnt put nowhere near as much load on it as the weber is. with the solex cracked wide open you probably still had 5-8 inches of vacumm with the weber your probably dropping much closer to 0 Hg.

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If it ain't broke ill fix that

the only thing i have seen a progressive weber run on is a toyota motor, never on a volkswagon..when we first started riding buggies 14 years ago, someone suckered us into putting dual progressives on and that was the worst thing we ever did and it was no better just using one of them. A buddy of mine recently bought a buggy and it had a progressive weber that was having the same problem your having, i finally talked him into boomeranging that thing into the woods and he now runs a single 36 dellorto with zero issues .. im sure the issue can be resolved, but IMO i would sell it to someone with a toyota truck and get a two barrel weber or dellorto

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LEGALIZE BLUEGRASS!!!

Save a tree... eat a Beaver

i ran a progressive for years on a few buggies...only problem i had was leaks around intake boots...DO NOT BUY THE RED AFTERMARKET BOOTS.....if you can find a good set of original black rubber style and be careful when you tighten the hose clamps down on them.....learned all this the hard way

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Hey,can you hand me those zip ties and that roll of duct tape?!

I just went through this issue. Its mainly your jetting. I'm running a 140 on primary and a 185 on secondary. A 55 primary idle and a 70 secondary. My engine is only a 1679 without preheat. It ran fairly decent with this setting until I got too much end play which is changing my timing. John at aircooled.net got me close on these settings. Maybe he might have some info on yours. And yes those jets seem huge but they work better than the small ones.

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When in doubt pray harder!

ok so heres the jets that were in mine
1st 2nd
main- 135 140
air- 160 165

I think the problem is obvious haha
thanks for the help!!

We have a 1641 with a weber and it runs and idles great last yearit we were playin aroun with it and it lost a lot of power reset point gap and adj timing 30 & 2000 rpm runs like champ again. Nick