I ran carbs on my 3.4liter chevy conversion. I would never ever want
to subject other people to the problems of which I ran afoul.
One of the fun problems was a very rich condition at idle which
created a perfect mixture at WOT. If I rejetted the carb for proper
running at low throttle/ low speed, I would go into fuel starvation at
high rpms (not a good thing).
Another problem was that I had to change up the rods and jets to pass
emissions. I was lucky that I purchased an Edelbrock carb with their
easy change fittings.
~I don't mean to totally da byen on anyone, but I really do not feel
that carburation belongs on a modern automobile.
For the same price, you could build a Megasquirt. :)

Sudhir

On 8/16/06, Mike Rouby <mikerouby@yahoo.com> wrote:
> Dennis,
>
>   Many valid points.  Some of those you make sound a lot worse than it really is, but granted the 'potential' is there for such issues.
>
>   As for the "preheat" issue with center mounted carbs, Weber makes a remote snorkel to suck heated air and resolve this issue.  If you live in a cold or rainy climate, I would highly recommend one.  Plus in the Vanagon application it may allow for better fitment anyway.
>   http://www.jameng.com/products/images/99217.090.jpg
>
>   I take it you're an EFI fan.  Thanks for the counterpoints.  Most appreciated.
>
> Dennis Haynes <dhaynes@OPTONLINE.NET> wrote:
>   I have had experience with many carb set ups for many cars over the years.
> While carburetors appear to be an easy solution to FI issues there are many
> drawbacks. Worse, most conversions do not address issues that OEM carb set
> ups used as early as the 60's. Most kits are strictly, make it run, limited
> use fair weather installations. Here is a list of features most kits for
> VW's are lacking.
>
> Throttle Dashpot or positioner! When the throttle is closed for idle, direct
> vacuum is used to draw a fuel mix through the idle circuit. If over running
> the engine such as going down hill, this device delays throttle closing or
> may even hold it open so that fuel is not directly sucked into the engine
> without some air for it to burn. Can we say backfire, raw fuel in cylinders,
> black smoke?
>
> Choke pull off/Heater! Moist after market either do not have chokes, or the
> choke is operated by heater element, not engine temperature. Further, start
> engine for short time, shut off while choke is still closed and throttle
> held open and gravity will empty the fuel bowl directly into the cylinder
> with an open valve. On the type 2, this is real fun as the entire fuel tank
> can drain into the engine. BTDT! Can we say Hydro-Lock?
>
> Idle Shut Off Solenoid! I like the lack of this one. Yea, go turn off the
> engine. After a long hard run, Hope you a manual trans so you can pop the
> clutch in gear and get it to stop Dieseling!
>
> Manifold heat! This is a real problem in winter with center mounted carb
> kits. The fuel will sort of puddle in the manifold. Can we say flat spot?
> Oh, no intake air preheat either. You drive along for 10-15 miles and the
> engine just stops. You coast to the side and a few minutes later it runs
> again like nothing ever happened, for another 10 miles. Vaporizing fuel +
> what? Refrigeration. Add moisture in air and can we say carburetor icing?
>
> EGR ports! Air cooled Vanagons will miss this one. Excess NOx, burned
> pistons.
>
> How about proper porting for 2 stage distributor advance?
> Crankcase Breather the works?
> Fuel Vapor control!
> Air filter with adequate flow and the ability to trap dirt!
>
> Oh, I can go on.
>
> Dennis
>
>
>
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