We have all done this: you get into a rhythm and know specific cars like specific fueling ratio. But why not see if the car likes a little more or a little less?

I recently did a few tests on a 2013 Challenger and found some great results by stepping away from what I knew worked last time. I did my typical .84 Lambda for the first pull and it was very happy with fueling, but I did not stop right there. I tested runs at .82, .80, .78 and .76. Lambda.

Honestly, the results were great! This car really liked where I expected it to be. I found .84 to be a really good lambda fueling ratio for this said car and I picked up almost 8whp over the lowest fueling ratio test done. That’s a pretty decent gain I’d say! 

So, I went to the next car, a 2012 Challenger, but this one was equipped with an Automatic Transmission. After running the exact same tests, I found this car liked .80 Lambda the best. Best power and torque there, and ran great. I repeated these tests multiple times over a few days on both for testing purpose and still came out with the same results.

Both of these engines had the exact same parts on them, a cold air intake of the same brand, and an exhaust of the same brand. And the engines were clearly the same. But they both wanted different fueling. While yes, the trans can change load a small amount, but so can the engine simply flowing air, a small amount different.

It's ok to test a few different fueling ratios to see what works best for you.