Probably the most frequently asked questions is how to get more performance out of a Magnum 3.9l V6 engine. While there’s a lot of people that go to extremes to get a few extra ponies, there’s a lot of basic things you can do to get the most out of your V6 when it comes to horsepower and fuel economy.

• The best bang for your buck mod isn’t really an engine mod, but it goes a long way when it comes to performance. And that’s the gears in your rear end. Typically they’re 3.55, which is ok for a daily driver, but for performance, a 3.92 or 4.10 is ideal. There’s not a huge difference between the two, except 4.10′s are usually cheaper than the 3.92′s (just because the 3.92′s are more popular). But either one will give you enough to make sure you’re putting all the power you can to the wheels. Anything over 4.10′s is just too much, unless you have some extreme mods to back it up.
• Second on the list is another mod that’s not so much an engine mod, but frees up a lot of ponies. That’s installing an electric fan. The stock mechanical fan is heavy and clunky, and makes for a longer time for the engine to get up to normal operating temp (180 degrees is ideal). An electric fan frees up about 5-10 horsepower simply by not having the big heavy fan to spin, but since it only comes on after the engine hits 180 degrees, you’ll be able to create more power at the ideal operating temperature.
• Next is the thermostat. Since the real sweet spot for these engines is 180 degrees, you’ll need to replace the 195 degree thermostat with a 180 degree. Ma Mopar installed a 195 for “emission purposes”, but having the 180 in keeps it in that sweet spot. Anything below 180 is going to trigger your check engine light, plus doesn’t do a lot more.
• Now we get to the nitty-gritty engine stuff. Probably the cheapest mod is changing the spark plug to an Autolite 3922 or NGK 2262. These plugs run a bit cooler than the stock, and helps keep temperatures in that 180 degree sweet spot. Don’t waste your money on platnums or milti-fire plugs, they’re really just marketing ploys that don’t do squat on the dyno.
• After the plugs, time to change the wires, cap, and rotors. The wires, pretty much anything over a 8mm wire will do. Accel, MSD, JBA’s are good, but the NAPA gold 8mm wires are perfect for the job, and won’t break the bank. As far as the cap and rotor, anything with brass contacts is ideal, so the NAPA gold caps & rotors are great. Accel has them too, but they’re exactly the same as the NAPA gold, just different box and higher price.
• Air intakes… well, where do I start. There’s a lot of air intakes out there, the K&N, AEM, Airaids, etc are ok for just bolt ons. But a lot of guys build their own, have different methods and theories, but theres a few common specs that everyone agree on. First is your actual tube should be at least 3″ diameter. Anything smaller is just too small, anything bigger is un-needed. The actual filter, well the bigger the better. I use a S&B 9″ cone filter with the open end placed right between the passenger side radiator support and radiator. By removing the rubber cover on the radiator support, cold air from outside has a perfect path to the filter. So if you use PVC, or an exhaust bend that’s ceramic coated like mine, the tubing is up to you.
• Throttle body is ovbiously the next part of the equation. You’ll need something bigger than the stock throttle body. 48mm is ideal for most V6′s, 50mm only if you have a lot of serious mods like heads or a cam. Anything bigger will actually cause you to loose power. Both F&B and the Fastman make great throttle bodies, I would highly recommend either one. Anyone else… I just don’t trust.
• And last but not least, exhaust system is probably the most important. You got good flow coming in with your air intake and throttle body, you need good flow going out. A good cat-back from Magnaflow, Gibson, or JBA is just what the doctor ordered, but for people on a budget, just changing out the stock muffler is just as good. Agian, a 2 1/2 in Magnaflow or Gibson fits the bill nicely. Anything bigger will not give you enough back pressure and will cause you to loose horsepower.

I know I never mentioned tuners, and there’s a reason why. While they do gain you a lot on a stock vehicle, they’ll gain you more on a vehicle that has the above mods done to them. Tuners are really the one mod that puts everything together nicely to give you the best performance. Simply put, a better base will give you better results. As far as brands, I highly recommend Superchips…. they’re just on the ball. They’re the only ones I’d use for an off-the-shelf tuner.

Don’t get me wrong, there’s a ton of other mods out there But these are the basics you’ll need when you get into the more involved mods like heads, cams, headers, superchargers, etc… more on that to come!