Forget throttle tip-in, driveability, and vacuum at idle. Set the thing on Kill Mode via thimble-sized fuel jets, disregard the power valve, and let the carburetor dump as much fuel as possible down the throat of the manifold--then let it rip down the track. But what do you do when you need to drive it home? Here's where some of those basic carb-tuning skills come into play.
In most cases, dualities contradict. Not with a carburetor, though. The beauty of these old-fashioned gems is their ability to carry out different duties with the turn of a mixture screw and the swapping of fuel jets. The carburetor's ability to exercise dual workloads is the sole reason they are still around. Don't fix what ain't broke, right? Carburetors are not only simple to work on, but with a little basic knowledge your pig could become a sleek cheetah. It's easy to upgrade various components, such as manifold swaps, nitrous, or even gear swap changes on the car; driveability needs to parallel these situations accordingly. In the world of high performance, that means setting the tune for the track but then being able to set up for street duties. This may mean a slightly lower idle or possibly a bigger power valve.
To showcase the basics of carburetor tuning, we plopped on an out-of-the-box Mighty Demon 750 carburetor onto a stroker 383 small-block at Vaca Performance and Dyno in Downey, California. It was there we were schooled by John McKindley on basic Demon carburetor functions. McKindley explained what to look for and how to adjust the Demon for the perfect street tune. So read on as we illustrate our findings to teach you a few new tricks--or maybe remind you of old ones--for tuning your Demon for the street.
Quick NotesWhat We DidTuned a Mighty Demon 750 (PN 5402020GC) for the street on a low-compression 383 small-block
Bottom LineGet your carburetor to work more efficiently and make more power with less fuel