As we’ve said before, one of the benefits of having your own dyno at your disposal is the ability to test performance gains on any change we make to a vehicle. One of those test subjects we have right now is a 2005 Dodge Magnum RT with the 5.7 Hemi V8. It shares a platform (called the LX platform) with the Dodge Charger and Chrysler 300, so if you have one of those vehicles you can expect similar results.
The first thing we always do is a baseline to see what we’re working with. In this case, the Magnum made 267HP and 304FT/LB of torque to the rear wheels. Stock motor HP from factory is 350HP, and in our experience Dodge suffer from a 20% driveline loss, so rear wheel HP should be in the 280-290 range. Ours could be feeling the old age effects of 267,000km, but nevertheless we carried on with our planned upgrades.
The first upgrade was to install a K&N cold air intake. Again, the Charger and 300 use the exact same intake, so expect similar results. Installation is fairly straightforward as well. K&N claims right on their website that they got a 21HP gain when tested at their facility, so obviously we wanted to put that claim to the test on our dyno. As expected, our results were not as good, but we did manage to gain 9HP but lost 6FT/LB of torque which totalled 276HP and 298FT/LB. You can watch the dyno test here. There are so many factors at play when claiming results, so take any claims with a grain of salt. We were pleased with what we achieved, so that’s what matters.
Our next upgrade was the popular muffler (or suitcase) delete. It’s an enourmous suitcase-sized muffler located in the middle of the underbody. The internet forums seem to have mixed feelings on whether this one is actually a benefit or even going as far as saying it decreases power. Once again, we put the Magnum up on the dyno to get first hand results. In our case, we saw a 0HP gain, but we gain back the torque we lost with the intake installation and added 3FT/LB more. So now we were up to 276HP and 307FT/LB. As an added bonus, it sounds amazing so we’ll call this mod a win as well! You can watch the dyno test here.
Our final test of the this point was a Diablosport tune. At the time we had 93 octane fuel in the car so we went ahead and selected the 93 ‘canned’ (or preloaded) tune from Diablosport using our InTune i3 Tuner. As a precaution, DO NOT use a tune for octane higher than you are using. You can cause serious damage to your engine! Back up on the dyno again, the Magnum made 281HP and 313Ft/LB, which was a 5HP and 6FT/LB gain. Overall, the 3 mods gave us a 14HP and 9FT/LB gain. Not a spectacular gain by any means, but it is a riot to drive! Watch the final video here.
We’re now approaching Winter, so any more testing will have to wait until Spring. Forums have suggested that the decreased power output is possibly a traction control issue. Traction control systems really hate the dyno since it only sees 2 of the 4 wheels turning. They say simply pressing the button to disable doesn’t fully take it off and that the only true way to disable traction control fully is to pull the fuse (NOTE: This is for DYNO PURPOSES ONLY! We don’t recommend doing this for the street). So we would like to test that theory to see if that is our issue. If that doesn’t work will be changing the plugs, coils and wires. Stay tuned until Spring unless we sell it in the meantime!