We have long heard rumors that the powertrain control module in the upcoming Mustang might be locked up like Fort Knox. Imagine our relief when we learned that tuning support for the 2018 Mustang GT is already part of HP Tuners’ latest software release — VCM Suite v3.7.x beta. That means people can start modding the next-gen S550 as soon as it rolls off the dealer lot!

“It was no more difficult than the other modern PCMs we support,” Eric Brooks, Ford Calibration and Development engineer at HP Tuners, said of cracking the code inside the new Mustang’s computer.

We recently dug into many of the improvements laid upon the latest Mustang powertrain, but in case you haven’t been keeping track, the big changes are the addition of the dual-fuel system — that fuses both port and direct injection — and a 10-speed automatic transmission.

“The biggest hurdle I see for tuners will be learning to control the new 10-speed automatic,” Eric told us. “The majority of the engine control remains the same. Some tables are larger than before, but otherwise it is the same.”

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Here’s a peek at how the 2018 Mustang’s powertrain control module transitions from port injection at idle and low RPM to direct injection as the RPM climbs. It will take larger port injectors and some tuning to help these cars support big power increases.

While the transmission might be perplexing for tuners, we are more intrigued with how Ford is handling the fueling balance between the port and direct injectors.

“The PCM blends between port and direct injection,” Eric said. “The port injectors are small. They are used for cold start and light-throttle application.”

Apparently the system really functions like a hybrid of the familiar port-injection V8s and their smaller EcoBoost cousins.

“The parameters controlling the port injectors are the essentially the same as those used by Ford PCMs of the past. The direct injection side of things is the same as all of the EcoBoost vehicles,” Eric explained. “The real difference on the 2018 is how the PCM blends the fueling from port to direct fuel injection (see screenshot). I see no reason that someone couldn’t disable the direct-injection side entirely and tune it like previous-generation Mustangs. Like the EcoBoost engines, the direct-injection side will be limited on how much it will be able to support.”

So, it sounds like there will be a way to tune these cars for big power, which is a relief for those who have battled with maxed-out fueling on direct-injection-only EcoBoost machines. However, all the extra data flying around inside that new PCM does make for a big piece of software inside.

“Compared to a 2017, the flash size is doubled,” Eric explained. “It is eight megabytes now, compared with four before. The newer Ford PCMs support compression, so that helps with write times. The tune file is essentially zipped up, before being written. We are also able to write just the calibration section of the flash, which saves a lot of time. It only takes about 30 seconds to write a new tune in. However, reading the PCM is much slower, and it takes around 18 minutes.”

Certainly it will be worth the wait to be able to tune the new Mustang for better performance. For more on the capabilities of the latest HP Tuners software suite, you can visit the company’s official site here.