Will changing the jets to larger orifices help my stage 1 455. It's stock right now. If changing the jets are any other pieces needed to do the change. Thanks
That depends on what you're jetting already is and what your engine wants. The best way to do this is to spend a day at the track with a number of different rod and jet sizes and keep changing them until you notice one set is the fastest. When you change adjust your mixture it would be a good idea to have a spare air horn gasket in case you damage it while taking it off.
If you haven't added headers or an aluminum intake, and the car doesn't ping, I'd pretty much leave it alone. GM spent thousands of hours fine tuning these things to get just the right combo of jets and rods, and the combinations are probably infinite. Those combinations that actually function well are far fewer in number. When you change jets (only can do the primary circuit - secondaries are fixed) a rod change is generally a necessity to maintain a similar part throttle fuel mixture to stock. If you don't maintain the part throttle ratio (especially if you get it too rich) you'll lose throttle response and fuel mileage. Make it too lean and you'll get detonation. Either way you'll be sorry. For the best explanation of this see the book Rochester Carburetors by Doug Roe. It is THE Q-Jet Bible. The secondary circuit is different and more easily adjustable but the primary is where most of your driving is done. You will see a serious seat of the pants and truly measurable performance improvement from modifying your timing curve. And - this is easier than monkeying around with the Q-jet primary circuit.
