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> Any Luck With Single Carb
rickso71
post Aug 29 2005, 08:18 PM
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I've seen the advice... dual carbs or FI... DON"T GO SINGLE CARB! I plan to return to FI, possibly over the winter, but unfortunately right now all I have is a single carb and it's not running very well and I want to drive the car for a while before winter.

Anyone have a single progressive carb setup that runs OK? Not looking for blistering acceleration just something driveable. My problem is giving gas off idle causes a stumble and I need to work the gas to be able to accelerate. Don't know if single carb can be driveable or if just something wrong with my setup. Have tried different settings of mixture.

The car is a '71 1.7L with Weber 32/36 DFEV.
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Joe Bob
post Aug 29 2005, 08:59 PM
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It's a continuous nightmare......
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eg914
post Aug 29 2005, 09:03 PM
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I have been living with the same setup for the last couple of years. I am also planning on going to stock FI this fall. I am currently using the car every day, including during our CA central valley winters. It is OK in the spring, summer, fall, and a dog in winter. Have you checked the idle speed and mixture? I don't seem to have too much trouble once the car is warmed up. My idle is set around 900 rpm, with the mixture set about 1/2 turn counter clockwise from a just smooth idle.
Sorry if this is not much help, but it can run well enough to be a fun drive in not too cold weather.
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bd1308
post Aug 29 2005, 09:10 PM
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it's a good setup.....well
depends on your engine size....

what size is your engine?

mine is a 1.7.....was told that anything over that would need a dual carb....

i'm waiting for the winter...
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URY914
post Aug 29 2005, 09:22 PM
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QUOTE (bd1308 @ Aug 29 2005, 07:10 PM)
it's a good setup.....I was told that anything over that would need a dual carb....


Stop listening to that guy.

Single carbs SUCK.

How many times do you have to be told??? (IMG:http://www.914world.com/bbs2/html/emoticons/smash.gif)
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eg914
post Aug 29 2005, 09:28 PM
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Mine is also a 1.7L. The single carb is a terrible induction system in the winter. The fuel seems to settle out of the air in the runners, and the car is very difficult to keep running. If its cold enough outside its like the car never warms up!
At other times of the year it is fine as long as I don't park for more than 15 minutes and less than enough for the engine to cool. The elec. choke likes to close before the engine is cold, and is too slow to reopen. This makes for a hard and smokey/smelly start. Once it reopens all is fine. Acceleration is adequate, and milage is OK. I've been averaging about 26 mpg on my daily commute.
No flat air cooled engine should have only one carb.
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morph
post Aug 29 2005, 10:19 PM
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you can make a single carb work on a 914.i drove for two years on one.you have to run rich to get it to work right with your motor.this is the reason why people recomend againts using one.YOU CAN MAKE A SINGLE CARB WORK.you just wont be doing your motor any favors in the long run or get anytype of performance/economy period,but you can make it run smoothly.i ran a dgav weber.make sure your ignition is all in order first.b4 you start on adjusting the carb.you may have to jet up to get it to work right.a single carb can get you by.till you get a better fuel system.
james
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Joe Bob
post Aug 29 2005, 10:22 PM
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Aw for Cryin' out loud....that carb was made for a PINTO!!!

Doesn't that tell you something?????
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bd1308
post Aug 29 2005, 11:37 PM
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i dont care either way....i'm staying out of this one. I'll watch


where's my popcorn?
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Mueller
post Aug 29 2005, 11:55 PM
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QUOTE (bd1308 @ Aug 29 2005, 08:10 PM)
it's a good setup.....well
depends on your engine size....

what size is your engine?

mine is a 1.7.....was told that anything over that would need a dual carb....

i'm waiting for the winter...

who tells you these things??

do you have a little BS fairy whispering in your ear at night???? (IMG:http://www.914world.com/bbs2/html/emoticons/wacko.gif)

that carb will flow enough to feed a motor up to 3800 cc's (depending on rpm of course)

it has nothing to do with size, it's the piss poor logistics of getting air AND fuel from the carb to the cylinders....

now back to the question...can you adjust the accelerator pump? (these should have "something" akin to that I would think???)...it sounds like it's starving for fuel at acceleration (which is why one person recommended to run the carb a tad rich)
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grantsfo
post Aug 30 2005, 12:03 AM
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I ran a real great t4 Bus engine on a single carb. Ran great and it was so powerful I could pop wheelies. It was even faster with dual carbs.
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Dr. Roger
post Aug 30 2005, 12:50 AM
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Hmmm, I ran a single 1 barrel weber in my 1.6 Ghia and it ran like a tank. Warm and cold weather. Zero problems. Dirt cheap. Bought it at Buggy House in Hayward, CA. Did I mention it was dirt cheap? Hot and cold? =-)

I did hear of a guy who heated his intakes in the winter... Didn't get the details though.

Quote from another website:
Are you running with the vacuum advance on the distributor? If so plug the vacuum hole in the carb and the line to the distributor and see if that helps. I tried using the vacuum advance without luck and am now only using the mechanical advance. I set my timing at 34 degrees total advance at 4000 rpm and let idle advance work itself out. This eliminated the stumble I had with my setup.

Hope this helps..

Oh and for the FI option. Hot VW mag just had a FI setup article in detail. Probably search for it. $3K with everything included. U install the O2 bung and the laptop for tuning.

Roger
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Dr. Roger
post Aug 30 2005, 01:01 AM
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Cold weather solution for the flat 4 engine. See "rear view" discription.
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ArtechnikA
post Aug 30 2005, 04:47 AM
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QUOTE (rogergrubb @ Aug 30 2005, 02:50 AM)
Hmmm, I ran a single 1 barrel weber in my 1.6 Ghia and it ran like a tank.

T-I manifolds have heat risers.

this isn't the best for performance but it's what you have to do to keep the fuel vaporised in a long-runner manifold.

i have no idea how to add a heat riser to a T-IV -- especially since there are real solutions available. (like the ones the engines were delivered with...)
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BarberDave
post Aug 30 2005, 05:41 AM
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All you guys with a 1.7 I have excellent F.I.set up on E-Bay now. Item # 7996678699. Also had a single Carb on the same engine, I have a big bore ,short stroke,engine with webers. If the F.I. could be modified to fit and run right it would be on there NOW. Good system for someone. Dave (this is a blatant commercial i know)
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rickso71
post Aug 30 2005, 06:19 AM
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Thanks for the ideas and suggestions. I'm running at 34 deg advance at 3K, have no vacuum line to the distributor (there is no port for it), and the vacuum hose plugged at the carb. THe carb primary seems to dump a lot of fuel when revved from idle so I think if anything I've got too much, not starved.

As for cold operation, not driving in winter (no heat exchangers) so not an issue.
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jr91472
post Aug 30 2005, 07:29 AM
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I have been running the single carb on my 1.8L for quite awhile. It is not ideal, BUT it has NEVER stranded me. And it ALWAYS starts. Mine was set up by a professional mechanic with lots of 914 experience. It also has an aftermarket cam (not stock FI cam.....it is my understanding that this make alot of difference).
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Joe Bob
post Aug 30 2005, 07:32 AM
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QUOTE (jr91472 @ Aug 30 2005, 05:29 AM)
Mine was set up by a professional mechanic with lots of 914 experience.

O....k.....lot's of 914 experience. (IMG:http://www.914world.com/bbs2/html/emoticons/wink.gif)
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morph
post Aug 30 2005, 08:05 AM
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you may have your advance set up alittle to far,try 30 /29 advance.
james
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bd1308
post Aug 30 2005, 08:38 AM
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PP's tech article on carbs states to set the advance to 35deg....
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