In the coming months we will be adding a lot of information on Weber carbs, concentrating most of our efforts on the progressive DGV's and DFV's, as well as the synchronous DGS's carburetors, all which are 2V down-draft carbs. However we'll also cover the DCOE Series side-draft carburetors, which are considered to be the ultimate induction system for any naturally aspirated engine. If your looking for unsurpassed performance, and eye candy that's second to none, check out our tech article on Triple Weber Induction Systems. On the other hand, if you're thinking about swapping out your stock one-barrel carb for a Weber 2V down-draft carb, this is a great place to start.
The first step is to decide which series is best suited to your needs, the 32/36 DGV or DFV, or the 38/38 DGS? In the past there has been considerable mis-information published, so we'll try to straighten things out the best we can. We'll give you a brief description of each carb series, the applications they are best suited for, the various installation options, and finally, the related parts that are available to complete the installation. We'll also help you learn how to re-jet and tune a Weber carb, so it runs properly on your engine.
The 32/36 DGV Series carbs were designed to provide an economical performance carburetor that increases power, improves driveability, and offers better fuel economy over the stock OEM carburetors. The DGV progressive carburetors are pre-calibrated from the factory, and set to run on stock engines. If the engine has been upgraded or improved with other performance items, such as a camshaft or increase compression, they may need to be re-calibrated or re-jetted for some applications. The 32/36 DGV is a progressive carb, so only the primary barrel is used for low speed operation. The secondary barrel only opens when additional air flow is required, for wide open throttle or high speed operation. As a progressive style carburetor, it offers excellent throttle response and fuel economy, as well as high end power when it's needed. The DGV's are an excellent 2V carburetor to use on stock and/or mild performance engines, and they are a great replacement carb for worn out or hard to maintain factory one barrel carbs. If your concerned more with mileage, low end power, and do a lot of city driving, this is the carb for you.
The DFV Series carbs are exactly the same as the DGV Series, but they are a mirror image, with the primary and secondary barrel positions reversed in the carb body. As such the throttle lever in the DFV rotates in a clockwise motion, rather then counter-clockwise, which may help you out when it's time to install the linkage. These carbs are available by special order only, and are non-returnable.
The 38/38 DGAS is a synchronous carburetor, meaning both barrels open simultaneously, or at the same time. The carbs are pre-calibrated from the factory and set-up to use on performance motors, as well as larger stock motors with 250 cubic inches or more. This provides the best starting point for engines that are ultimately going to be upgraded with additional performance items, with performance being the ultimate goal, rather than fuel economy, low end power, or throttle response.
While synchronous carbs offer considerably more torque and acceleration over the 32/36 DGV, throttle response and driveability may not be as good. Top end performance on a stock motor will not be significantly improved, but the additional cfm's are great for a motor that has been modified. By modified, we mean with headers, free flowing exhaust, performance cam, increased compression ratios, and a large log head or a cylinder head that has been modified or reworked.
While the 38/38 DGS carb will work on stock un-modified engines, we only recommend installing them on a 250ci or larger, as they may be a bit to big for a stock 170 or 200ci. The exception to this would be a stock 200ci which is used primarily for highway driving, where throttle response and low end power isn't a concern, as the larger carb would give you more top end power for cruising and/or passing.
We won't go into the Weber Side-draft carbs in this article, however we do have a separate article that covers the installation and tuning of Triple Weber Carbs, which is the ultimate set-up for our Aluminum Cylinder Head.
The 32/36 DGV's and DFV's are perfectly suited for stock or mild performance engines, where fuel economy and driveability are the primary concerns. They are the perfect carb for those who are looking for increased performance, over the stock one barrel carb, without having to sacrifice throttle response and/or driveability.
On the other hand, the 38/38 DGS is the optimum choice for performance applications, as it incorporates a larger fuel delivery system and is calibrated from the factory to handle a broader range of performance enhancements. Performance engines may require additional calibration and re-jetting to attain the best performance and fuel economy. As such, jetting kits are available for both the DGV and DGS series carbs. It should be noted that the 32/36 progressive carburetor normally improves fuel economy on a stock motor, over the OEM carb, while the 38/38 DGS usually gets about the same fuel economy, or slightly better. Certainly not less in either case, providing it is tuned and adjusted properly. The 32/36 DGV is a great choice if the car is used primarily for city driving, whereas the 38/38 DGS may be a better choice if you spend a lot of time on the highway, where more top end power is desirable.
There are two methods being used to install 2V carbs on a 1V log manifold. The most popular and easiest is using a 2-1 adaptor, where the air flow is funneled into the existing 1V opening in the log manifold (carb bore). The other method, called a 2V Conversion, requires removing the cylinder head from the motor, milling the log manifold, and converting it to a true 2V opening. Our tech article on 2V Carb Swaps covers both methods in detail. You may want to read our tech article on Dyno Testing, as it has a lot of useful information as well.
Tuning and Adjusting
Please see our tech article on Tuning and Adjusting Weber carburetors.
Service Parts & Rebuild Kits
In this section we'll cover the various service parts and rebuild kits that are available to get the best performance from your Weber carb. CURRETLY UNDER CONSTRUCTION....
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