Should I install a 32/36 DGEV carburetor or the 38 DGAS?

First off, the kits that use the 32/36 Progressives Weber are engineered to give customers an economical performance carburetor conversion that simultaneously increases Hp,  improves drivability, and fuel economy over the stock carburetor. The kits utilizing the 32/36 progressive carburetor are the optimal choice for the replacement of a worn out or hard to maintain factory carb.   

However, when the REDLINE kit with the 38mm DGAS carburetor is installed it will also perform on a stock unmodified engine without any problems such as over carburetion. The 38mm DGAS carb will provide considerably more initial acceleration and torque but top end performance will not be significantly improved over the 32/36 on an unmodified stock engine.

If your engine currently has or will have any level of modification, such as headers, free flowing exhaust, performance cam, or is a rebuilt engine then the 38mm DGAS carburetor should be the only consideration. These engines are usually enhanced over stock conditions with oversized pistons and towing cam, and the 38mm will further enhance the improvements of any of these items

When you are using a 32/36 in the above scenarios it requires additional calibration and rejetting to obtain the desired performance and standard fuel economy. There is a jet kit available for just this purpose. The jetting is required due to the performance enhancements of the additional modifications. Although the 32/36 does outperform the original, to receive the maximum benefit of your investment the 32/36 will require helpful re-calibration. The 38 DGAS is the better choice and has a larger fuel delivery system and the calibration to handle the broader range of improved performance and improves substantially your other product investments.  

Although the 32/36 progressive carburetor will improve your fuel economy of your stock engine over the OEM carburetor. The 38 Synchronous carb will not get less fuel economy than the OEM carb.

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