

| Subject: | Re: Carb conversions? |
| From: | Mike Rouby |
| Date: | Wed, 16 Aug 2006 17:31:37 -0700 |
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 --------------------------------- Do you Yahoo!? Get on board. You're invited to try the new Yahoo! Mail Beta.
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