Tuning the Explorer ST - There is no better first mod.

It's not hard to believe that tuning is the single biggest bang for your buck modification on the Explorer ST. With a stout 3.0 liter twin turbo setup, there's plenty of boost on tap from the factory hair dryers to go out and hurt some feelings on your way home from your kids' soccer practice.

I originally had a Mustang S650 picked out as my next project. It was sitting in the garage just begging to be tuned and modded. But the tuning never came and who knows when it will. It could be 3 weeks or 3 years. I'm leaning towards the latter. I moved on to the Explorer ST platform since tunability isn't an issue there and I had a growing need for a family friendly vehicle. I have tuned thousands of EcoBoosts from Focus STs, RS', Fiesta STs to F-150 Raptors and more. So, this seemed like a natural choice getting into another EcoBoost platform.

Before tuning, I wanted to make sure to set a baseline of where I'm starting. It's always fun to know how far along a car has come. But for tuning purposes, it's important to know where you stand at any given point compared to what you're starting with and where others are at with similar modifications and tuning practices. The Dragy is a perfect way to do this.

I was extremely impressed with the out of the box performance. With a little more effort, I probably could have gotten a little quicker. But this was on the way home from the dealer, with a brand new ST. 

A sub 14 second quarter mile is about all you can ask for from such a large vehicle designed to haul around the family and all the baggage that comes with.

Knowing that I was going to be getting the Explorer, I had purchased a Cobb Tuning Accessport as they had recently released support for Explorer ST. As soon as I received it, I went out and started my testing and below are the results of the Stage 0 (stock file) compared to the Cobb OTS Stage 1 map plus sport trans for 93 oct fuel.

Stock power came in at 377whp and 428wtq. With the addition of the AccessPort and Stage 1 93 oct map, we see significant gains of 42whp and 55wtq for a total of 419whp and 483wtq. This allowed me to drop my dragy quarter mile time by 0.76 seconds!

This is pretty impressive all on its own and if you never took it further than this, the Explorer ST would still be plenty enjoyable. But being a tuner, I can’t leave well enough alone… So, I turned it up.

Below is my custom 93oct tune compared to the Cobb OTS map along with the stock (stage 0) map.

As you can see, there was certainly room left on the table to make more power with massive gains throughout the powerband. Horsepower increases by 104whp and torque increases by 98ftlbs. The total power/torque is 481whp and 526wtq. With these changes my quarter mile Dragy time improved by another significant margin dropping my over all time by over a full second down to 12.74 seconds @ 107mph. 

One of the caveats that I ran into that a lot of Explorer ST owners will be familiar with is that my transmission was underfilled. This killed a lot of my early testing due to the trans not wanting to shift from 1^st to 2^nd gear. My launches were slow and my 0 to 60 times suffered until I was able to do a flush and fill and get it where it needs to be. Once getting the trans fluid where it needed to be my 0 to 60 dropped by three tenths of a second. As of the writing of this blog, I have not yet gone back and tested on 93 oct with a filled trans.

Many people would be happy with leaving it here. 481whp is no slouch by most people's standards. Being able to go to a standard gas pump, put 93 in the tank, and send it that hard in your family vehicle is pretty wild!

But knowing what ethanol can do on any given platform, it was definitely something I wanted to mess with, especially since more power is available still, without modding anything but the tuning.

With just a little ethanol in the tank we see another bump in horsepower of 30whp and 61wtq. This makes for total gains from stock of 134whp and 159wtq. And obviously, with more power comes another Dragy pull... this is where I really started to suffer with the trans. It would not shift from 1st to 2nd cleanly until I did a flush and fill. Here is the Dragy pull with the trans topped off. 12.44 seconds @ 109.75 mph.

There is more to be had in this setup even with a completely stock vehicle, but rather than show you the all out max effort "what can be done", I'm leaving this as a safe map that will be totally fine as a daily or on the race track. 

If you're like me and you've convinced yourself it's okay to do this to your family's primary mode of transportation, please feel free to reach out to tuning@edgeautosport.com with any questions. I'd be happy to get you taken care of! As you can see, a lot can be done with just a tune...

If you're interested in more information or you already know you're ready to start tuning your Explorer ST, here are some helpful resources.

If you want to see more on the Accessport, check out our youtube channel here where we covered install and initial tuning.

If you're the type that wants more than just a tune and you're wondering what's next for your Explorer ST, check out the next part of our series. If the Accessport and tune is the first mod, the upgraded front mount intercooler should be your second. Extremely high charge air temps have been plaguing this entire process thus far and I can see very well that an upgraded intercooler will be a massive benefit.